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IN THE December issue of MINING AND METALLURGY, attention was drawn to the February meeting of the Institute. The plans of the Committee on Arrange-ments have progressed considerably since that date, so that further announcements may now be made. The Mining Methods Committee has definitely arranged for at least three sessions. One of these will be devoted to a discussion of various methods used in sampling large low-grade ore deposits; a second will have for its leading subject underground transportation and mining practice as developed by the Anaconda Copper Mining Co., and the third will be devoted to the coal industry, particularly in reference to the percent-age of economic recovery under various conditions. The Mining Methods Committee will also hold a committee meeting, which will be open to all members, for the purpose of a discussion in reference to the symposium on mining methods which it proposes to hold at an early meeting. The Petroleum and Gas Committee is planning a two-day symposium. A tentative program was printed in the November number of MINING AND METALLURGY, and this, with a few changes, still indicates the plans of the committee. E. L. DeGolyer, vice-chairman of the committee, says Mining engineers and geologists should make every effort to attend the February meeting and hear the symposiums on foreign oil possibilities which have been arranged by the Petro-leum and Gas Committee of the Institute. No such comprehen-sive consideration of this subject as that planned has previously been attempted. This matter is extremely important to all persons who are users of petroleum or its products, and in our present civilization this classification includes every individual, but it is particularly important to the engineer who directs the production and use of power on a large scale. The United States produces currently about two-thirds of the world's oil but consumes more than it produces. We must look .to outside areas for part at least of our petroleum requirements and the future market, because even American oil will be influ-enced largely by the ease and freedom with which this outside supply may be secured. It is important to you to know something of foreign prospects and conditions under which they may be developed.

Jan 1, 1922

By Richard Moldenke

The author discusses some economic conditions which have made the career of the cast-iron pipe industry in the United States a checkered one. He next describes the two new developements in the manufacture of cast-iron pipe-both along the lines of centrifugal casting. The advantages and disadvantages of both processes are presented in some detail. Finally, statistics on the production of pipe in the United States at the present time are given, as well as the plants-and their capacities-so far as these are situated in the South. No SINGLE branch of the foundry industry has been brought to a production basis of huge tonnage, low manufacturing cost, and producing material of a remarkably high quality, as has the making of cast-iron pipe. The pipe shop is an excellent illustration of the fact that repetition work in specialties leads to mechanical equipment and manipulation that lower production costs to an. astonishing degree. Hence cast-iron pipe, in dull times, has been sold at a few dollars a ton over the selling price of the pig iron used. On the other hand, these same pipe, shops make fittings .of many varieties, and in much smaller quantities, where the cost is high, and when pipe may be sold, say, at $50 a ton, the fittings on the same shipment will be sold for nearly double that price. The history of pipe-making, in the United States, is a checkered one the mortality of plants is high and, from the nature of the industry, plants must be large to live. In spite of the fact that the best processes must be used to turn out this rather strict specification material, pipe is easy to make and a pipe plant is more of a tonnage mill than the really high-class specialty foundry it should be. Every time, therefore, that the demand for pipe is strong new shops spring up, only to close when the demand has ceased, but the financial damage to the more permanent plants has been done. Both the South and the North have had abundant experiences of this kind, and when recently a northern Public Service Corporation gave its order to France, the pipe plants thus adversely affected were content to have this occur rather than see-a plant started to supply the surplus demand.

Jan 9, 1924

By Thomas M. Drown

The use of bromine as an oxidizing agent, particularly for sul phur, has become very general in analysis, replacing the stronger oxidizing acids. The object of this paper is to describe briefly the experience which we have gained with this reagent in the laboratory of Lafayette College in the oxidation of metallic sulphides. Most of the simple sulphides, as blende, pyrite, etc., when exposed to the combined action of an alkaline hydrate and bromine, and finally to hydrochloric acid, are completely and promptly dissolved. The procedure is as follows: The very finely pulverized mineral is first treated, in a beaker, with a solution of sodium hydrate of a spe cific gravity of 1.25, and heated ; bromine is then cautiously added to supersaturation, and finally hydrochloric acid to acid reaction. If any of the sulphide is not taken up, the same operation may be re peated. It is necessary, however, that the mineral be very finely pulverized. Instead of using the pure bromine, a saturated solu tion of bromine in potassium bromide may be used with equally good effect. The process is advantageously simplified by making a saturated solution of bromine in the concentrated alkali. This is done by pouring bromine into a solution of sodium hydrate, of the above given specific gravity, until no more is taken up, and then adding a little of the sodium hydrate solution until the liquid does not give off free bromine. The procedure with this solution is as follows: The pulverized mineral is moistened with, say, 10 cc. of the solution, and heated, then hydrochloric acid added to just acid reaction. Two more additions of the alkaline solution, in amounts of 20 cc. each, are added at intervals of about ten minutes, each addition being followed by hydrochloric acid. The total amount of the alkaline solution (containing the bromine) used is, therefore, 50 cc., and the amount of hydrochloric acid should not exceed that necessary to make the solu tion acid after each addition of the alkali. The mixture should be kept hot. After the final addition of acid, the contents of the beaker is taken to dryness and heated in an air-bath to 110° to 115°C., to render silica insoluble. The dry mass is then taken up by hydro' chloric acid and water and, after filtration, the sulphuric acid is pre

Jan 1, 1880

By W. W. Anderson

John Griffen—The author has called attention to an important phase of coal cleaning since there has been considerable loose thinking regarding efficiency formulae and particularly inaccurate application of ones that have been advanced. The unanimous acceptance of an efficiency formula has been prevented because the issue has been beclouded by the fact that the objective of cleaning—-the control of chemical characteristics of the coal such as ash or sulphur content—is attained by an indirect rather than a direct method. The indirect method is usually to effect separation according to differences in specific gravity. Such separation relies on the fact that the desired chemical qualities are roughly inversely proportional to the specific gravity of the particles being separated. However, the sulphur content of the materials found in raw coal usually exhibit a far from straight line relationship with their specific gravities. Mr. Anderson meets this issue squarely by basing his formula on the efficiency of separation according to specific gravity only. It is true that machines that effect primarily a specific gravity separation are in no way directly influenced by the chemical analysis of the materials being handled and it can be argued that it is illogical to measure their efficiency by any criterion other than that of separation according to specific gravity. For the moment, let us accept this basis and analyze the application of the efficiency conception and formula proposed by Mr. Anderson under conditions which he has not considered but that will readily be found. Let us take the separation shown in his table III as an example. He terms this an example of a high order of quantitative efficiency. We will show the weight distribution of the various gravity fractions as between clean coal and refuse in table XV. Only in the gravity range of 1.50 to 1.70 has material been misplaced and, on the assumption that the cleaned coal and refuse are equal in weight, Anderson shows a quantitative efficiency of 99 pet. The gravity of separation is 1.60 and one third of the 1.50 to 1.60 sp gr fraction is misplaced in the refuse while one third of the 1.60 to 1.70 sp gr fraction is misplaced in the cleaned coal. Let us now see what effect the gravity distribution of the total products has on the quantitative efficiency calculated by his formula. Still using the data in table

Jan 1, 1951

By H. F. Moore

AT PRESENT, I am connected with an investigation of the so-called fatigue of metals under stress. So far we have studied the more fundamental and simple case of the repeated stress, without the additional complexity of impact, which might bring in other factors. We feel that this investigation, which has been in active progress for a little over a year, has shown more conclusively than has been shown before that steel under repeated applications of stress, reversed from positive to negative, will not fail below some fairly clearly defined limiting stress that,, so far we can see, does not bear any definite relation to the ordinary elastic limit, being as large as the elastic limit in some cases and about one-half the elastic limit in others. I might be asked, first, what is fatigue. The old view is summed up "in the word "crystallization." The idea was that under repeated stress the material changed its crystalline structure. I do not know of any evidence in favor of the theory that metals materially change their crystalline structure under repeated stress. The crystals are broken under repeated stress. The second theory, advanced by Bauschinger, the German scientist, is that under repeated stress some inherent property of the material changes its elastic limit; it is an inherent property of the material, possibly some property of the amorphous cement between the crystal. The third view is that all fatigue of metals is the result of the spread of damage from little localized overstresses. I do not feel justified in stating my positive belief in the third view as against the second, but I have yet to run across a case of failure of steel or other metal, either in the laboratory or in service, that could not be explained by the gradual spread of damage from some nucleus. We have found, for example, that it is possible to subject a homogeneous steel, like Armco iron or a 0.90 per cent. carbon steel, that hag been thoroughly annealed, to one hundred million reversals f stress as high as the elastic limit of the steel with no sign of failure. We stopped the test at one hundred million because the machines Were required for other work. Forty-five days, continuous running at 1500 revolutions a minute is required to produce one hundred million repetitions. On the other hand, a complex structured steel, like a chrome-nickel steel that

Jan 6, 1921

By T. Sterry Hunt

At the meeting of the Institute in Easton, October, 1873,I made a communication on the Ore Knob copper mine, in Ashe County, North Carolina (Transactions, vol. ii, p. 123), in which I called attention to the chemical decomposition alike of the pyritous lode and the inclosing gneiss rock to a depth of 60 feet, by which the feldspar of the latter had been converted into clay, and the whole rock very much softened. Such a decomposition is well known to be almost universal in the crystalline rocks of the Appalachians south of the Potomac; and if it is only seen in rare and exceptional cases farther to the northward, this, as I have elsewhere pointed out, is due to the fact that the decomposition began and ended in the ages anterior to the drift period, and that the decayed portions which still remained were at that time removed from the surface, except in some localities which were protected from the emding agency. I have lately had an opportunity of studying a remarkable instance of this kind in an examination made last month for the corporators of the Hoosac Tunnel.* The locality is at the western base of Hoosac Mountain, the western slope of which rises rapidly 1300 feet above the town of North Adams, in Berkshire County, Massachusetts, itself 700 feet above the sea level. Through this mountain, as is well known, a tunnel for the Troy and Boston Railroad has lately been opened, a distance of 25,081 feet from east to west. The rock of the mountain consists of mica schist and micaceous gneiss, including in its western half a great mass of harder feldspathic and quartzose strata in part a granitoid gneiss, the strata for the most part dipping to the eastward with variable angles, but with occasional western dips, apparently due to inversion. The crystalline strata of the mountain crest and sides are in many places exposed, and present rounded surfaces, often deeply grooved and striated, but with no appearance of decay. At the western base of the mountain, however, the gneissic rock is in a state of complete decomposition, which was well displayed in opening the tunnel, which, for a distance of several hundred feet, was driven through highly inclined strata so much decomposed that they were excavated with pick and shovel, and without the aid of blast-

By A. R. Ledoux

I WAS wondering whether we were going to adhere to our text. It seems to me that we are having a very remarkable meeting of mining engineers this year, because no matter what the texts may be that are assigned to us, we get back toward something higher; we turn to the consideration of questions of ethics, and of applied Christianity. Yesterday we listened to the most eloquent and remarkable address by Mr. Rickard in memory of Dr. Raymond, and it was told us that he was to speak about Raymond's achievements as an engineer. He did say considerable on that subject, but he was himself carried away with the spirit of the man and moved us all by his portrayal of Dr. Raymond's continued and fruitful labors for the betterment of mankind-that is to say his religion. Our President asked me if I would say something this afternoon and I find in the bulletin that the text of the discourses which we are to have here this afternoon is "International Cooperation in Mining in North America." But again I find that the eloquent speaker who has just preceded me has dwelt largely on ethical and spiritual cooperation rather than upon cooperation in mining. That is, cooperation as men, rather .than solely as engineers. The imaginary line dividing Canada from the United States, unmarked by fort or military post, was mentioned by a previous speaker. There are going to be in the future, I am sure, fewer entanglements of the barbed wire of tariff discrimination along our border-to that end let us cooperate. But there has always been a reciprocity in men. A Canadian conceived and created our great transcontinental line, the Great Northern Railway; an American made the Canadian Pacific what it is. In mining and metallurgy, American engineers, backed by American capital, have built up great Canadian industries while Canadian experts have developed some of the resources on this side of the line. They have done much more than develop our resources: some of them have been our leaders in sympathy for labor. It is therefore not a question of creating a spirit of cooperation, but of giving it freer scope and a fuller realization of fraternity-or, to use the .word now more common and of deeper significance-brotherhood.

Jan 4, 1919

By James Munroe

APPALLING as has been the loss of life in the last 51 months, there is one slight compensation : no longer will there be in the world a cripple, in the old meaning of the term. Men handicapped by wounds or disease, there will be, unfortunately, and in numbers beyond what the world has known since the wars of Napoleon; but neither they nor the industries from which they were called off to war will be "crippled" in the sense in which both would have been had mankind not learned the lesson of conservation and come to understand that the most important field for such conservation is not in the forests and' the mines but among men and women. From the beginning of the Great War, France, Great Britain, Belgium, and most of the other Allies have studied the problem of restoring the soldiers and sailors injured through war to physical and economic efficiency; and from their experiences, especially from that of Canada, the United States has learned much. Consequently, our task of preparing for the return of our disabled men has been easier and, in some ways, more comprehensive than theirs. Complex as are the details of the machinery which the United States has set in motion to take care of the men injured by wounds or disease, the plan itself is simple. Taught by European experience, the Surgeon-General of the Army and the Bureau of Medicine and Surgery of the Navy have provided, on both sides of the Atlantic, every known surgical and medical facility for restoring the injured or diseased man to a physical condition as nearly normal as possible. While in the hospital in France or England, on the transport coming to America, and in the hospital here, the disabled man is incited in every way to believe in his future efficiency, to want to be a normal worker, to desire to retake his place in that society of workers from which he went, temporarily, to do the greater work of preserving civilization. Furthermore, since purposeful occupation is now regarded as an essential form of, treatment with most men in the hospital, especially in the convalescing stage, many of these men will have been actually started on the road to earning before they are discharged from the army surgeon's care.

Jan 1, 1919

By R. R. Webster, H. T. Clark

I. A. Sirel—I would like to ask Mr. Sims what would the preferred hot metal analysis be as far as manganese and silicon are concerned if you used specially made iron for this process instead of basic iron. C. E. Sims (authors' reply)—A preferred composition would contain somewhat less silicon than the basic pig iron used in these experiments. High silicon requires a large lime addition. Lime must be added in sufficient quantity to neutralize the silica formed and to leave an excess for dephosphorization. Manganese presents almost no problem in operation. It is almost completely oxidized and, in burning, develops considerable heat. The evidence indicates, however, that, in continuous commercial operation, there will be an excess of heat produced, and the bath will need to be cooled in some manner as by the addition of scrap or by utilizing the energy for the direct reduction of ore. There do not seem to be any serious limitations on composition of pig iron. One heat was made with an iron containing 2.27 pct silicon and the phosphorus finished at 0.007 pct. In another, the iron contained 0.45 pct phosphorus which was lowered to 0.019 pct. This indicates considerable leeway in composition. D. R. Loughrey—We are all very much interested in the recent discovery of very large deposits of iron ore both in Labrador and in Venezuela. I would like to ask Mr. Sims if the iron ore at either or both of these places is such that it would lend itself to the manufacture of iron suitable for use in the turbohearth. C. E. Sims-—According to my information, those ores are not essentially different from ores now used in this country for making basic pig. They should, therefore, be adaptable to this process. D. I. Brown—You have spoken about the leeway, or spread in analysis of the various irons you can use in the vessel. I would like to have you tell us, if you can, about the different kinds of steels which can be made in such a vessel. The turbohearth process, or it might more aptly be called pneumatic openhearth, is a little different from that used in most Bessemer shops and in the one in which I worked. If we had a blow in the air over 10 min, the boss was in the pulpit in a hurry

Jan 1, 1951

By D. W. Fuerstenau, J. H. Brown

The paper by Professors Sun and Mitchell illustrates the value of ultrasonics as a tool for the mineral engineer. In particular, it opens up a number of possibilities to those interested in the field of comminution. The provision of desliming technique, which is thorough as well as rapid, is a distinct contribution, but the data of the paper suggest applications beyond desliming, in that the same treatments may be useful for size determination purposes. Fig. 1 shows that a marked dependence exists between particle size and the height to which it can be elevated by ultrasonic vibrations. While the curves are only extended down to a size of about 100 u, the fact that they appear to be increasing in slope in this range suggests that the separation may be even more marked here. This, we feel, is very strong evidence that a nlethod for fine sizing could be developed to use ultrasonic waves as the separating force. Professors Sun and Mitchell indicate that floccula-ti~n will present no difficulty: "During the investigation it was found that ultrasonic waves were able to dislodge the adhering gangue particles from the min- era1 surfaces and to disintegrate the soft particles into fine sizes." Thus, it appears that the use of ultrasonic waves as the power behind a size separation process may eliminate the problem of flocculation encountered in most wet sizing techniques. It would be interesting to size a fine material under conditions in which particles are known to be flocculated and under conditions where they are known to be dispersed. Use of a sizing technique of this nature may solve several problems that have long persisted in the fine sizing field. The flocculation problem may be overcome; the continuous production of closely sized fractions may be possible with a device similar to the one described; and with photoelectric methods, rapid analyses in the subsieve sizes may be possible. In general, we suggest that this paper be followed by a study of the sizing applications of the apparatus described. We feel that such a study would not only be rewarding in providing a new sizing technique, but also that the present paper almost requires such work to complete the picture of particle motion in a field of ultrasonic waves.

Jan 1, 1958

By S. J. Leach

The possible solution of some of the problems raised in H. L. Hartman's article "Determining Ventilation Requirements for Continuous Miners," which appeared in the March 1962 issue of MINING ENGINEERING, is offered by recent investigative work done at the Safety in Mines Research Establishment, Ministry of Power, Sheffield, England. Highlights of this research are outlined here. Accumulations and layers of methane form in a mine roadway because it is difficult to mix methane with air beneath it by turbulent diffusion. Such mixing involves work contrary to buoyancy forces. In specifying requirements for good ventilation it is not, therefore, sufficient to state that the airflow must be turbulent in the absence of methane. Fundamental work at SMRE on the behavior of methane roof layers has led to the formulation of rules for controlling methane roof layers which specify the ventilation velocity needed to ensure adequate mixing in terms of the rate of flow of methane into the layer (V = cu ft per min) and the airway width (D = ft). A "layering number" for methane and air has been defined by [U37/V/D] where U is the mean ventilation velocity in ft/min in the upper half of the airway. In a horizontal airway there is no mixing by turbulent diffusion for values of the layering number less than about 2, resulting in extensive roof layers. But with a layering number of 5, the layer is "brought under control"-i.e., a further increase in the layering number will shorten the length of the layer only slightly, and a small decrease in the layering number will cause only a small increase in the length of the layer. In a sloping roadway with uphill ventilation, higher values of the layering number are needed to achieve this "controlled" condition; the values range from about 5 at small slopes to about 8 at a slope of 1: 10. In downhill ventilation it is possible for layers to "back" against the ventilation, i.e., to flow uphill. The critical condition for preventing backing can also be expressed in terms of the layering number. Backing will be prevented if layering numbers are about 3 for small slopes and about 4.5 for large slopes; these values for downhill ventilation also give good control of the layer.

Jan 10, 1962

H. M. BOYLSTON, Cambridge, Mass.-I would first like to ask what machine Capt. Bellis used to make his tests on impact strength. I have made some tests with the Charpy impact machine, the specimen being supported at both ends and nicked in the middle, and, find that the results do not always agree with those obtained by the Izod and other machines. I would also like to ask what effect the composition and heat treatment of the tool steel had on the drilling of his rifle barrels, as compared, with the heat treatment of the steel itself? I notice that the analysis of the composition of steel used shows sulphur 0.050 and phosphorus 0.065; I should like to ask how those high limits of sulphur and phosphorus came to be allowed? I have some data which lead me to feel pretty certain that those high limits make for very unsafe steel in rifle barrels. It has never been explained to the satisfaction of all of us, why the manganese is so high: 1.22 per cent. I believe several reasons have been stated; among them, that it is high in order to compensate for the high sulphur, and also to increase the elastic limit and improve other physical properties of steel. Lastly, I wish to ask whether Capt. Bellis has tried any different methods of heat-treating his steel rifle barrels? Apparently these were all heat-treated before machining; has he had any experience with heat-treatment after machining, especially after drilling? Those questions may seem somewhat outside of the range of this -paper, but they are important, and if Captain Bellis can give us any information, it will be very helpful. Dr. J. A. MATHEWS,* Syracuse, N. Y.-The same subject was discussed here last year, and the earlier papers by Dr. Carle Hayward seem to indicate that nothing was gained by the length of time of 'tempering. (It should be borne in mind that his results were based upon electrical and magnetic measurements and not upon tensile tests.) That idea has been accepted as gospel by steel workers, until late years, and particu-larly in connection with alloy steels, on which there is no question that the effect of time of tempering is very marked.

Jan 4, 1918

By Edward Gridley

Members of the Institute who were present at the Amenia, N. Y., meeting, in October, 1877, will remember their visit to the hematite mines, just west of the village of Amenia, and some of them may perhaps recall the deposit of carbonate ore south of the opening made for the hematite. The smelting of this carbonate during the last few months, has produced an iron that seems worthy of being brought to your notice. A little more than a year ago, at the Wassaie Furnace, Dutchess County, N. Y., we made a few hundred tons of iron from a mixture of two-thirds ram carbonate and one-third Chateaugay ore, hoping that it would be suitable for steel purposes, but as the iron showed phosphorus 0.189 per cent., it, was not offered. This iron looked well and seemed quite strong, and gave good results in malleable castings; but no special tests of strength were made. About February 1st, of this year, we began using two-thirds roasted carbonate, and one-third Chateaugay, and noticing that the iron mas stronger than usual, we had two samples tested, which showed tensile strength of 32,014 and 34,176 pounds per square inch. After our stock of Chateaugay ore was exhausted, me put on one-third ram carbonate with the two-thirds of roasted carbonate, and the first test made of the iron, showed 40,008 pounds per square inch. The three tests given above were made by Mr. A. J. Copp and Mr. E. B. Manning, of the Phoenix Furnace, Millerton, N. Y., on a machine of Riehle Bros., Philadelphia. Since these tests were made, they have broken samples made with all carbonate ore as follows: 39,669, 40,816, 41,882, 42,281, 39,902, and 40,130 pounds per square inch. A test taken from the same bed of iron as the last-mentioned (40,130), was broken by Mr. A. Blass, at Irondale Furnace, showing 40,151 pounds per square inch. A sample broken on the Riehle Bros. machine, at Stevens Institute, under direction of Professor R. H. Thurston, showed 40,000 pounds per square inch. Another sample was broken by Professor Thurston on his torsion machine, and gave torsion 7", and tensile strength of 44,500 pounds. And

Jan 1, 1884

By Felix B. Shay

THE Agua Fria mine is in eastern Honduras at Lat. 140° 06' N., Long. 86° 36’ W. Danli, the seat of the local municipal government, is the nearest town. The property is approximately 44 miles east of Tegucigalpa, the terminus of a truck road from the Pacific coast. The mine lies at an altitude of 3300 ft. with surrounding elevations as high as 6000 feet. For 20 years the oxidized croppings of the Agua Fria vein had been worked intermittently when in 1927 an attempt was made to open the property. A shaft was sunk 300 ft. and considerable ore was blocked out, but before a mill could be installed financial difficulties arose and the mine reverted to the original owners. Erle P. Halliburton, of Los Angeles, purchased the property in 1934. At that time a careful consideration of all factors involved showed that air transport was the only practical method of moving the equipment and machinery necessary to commence production. The other alternative was by muleback, which required sectionalizing all equipment to a maximum load of 200 lb., and during the rainy season this type of freighting was subject to serious delays. It was decided to purchase a trimotor Ford powered by three Pratt and Whitney Wasp B motors developing 400 hp. each. There were several reasons for the choice: (1) this type of plane was available at a reasonable price, owing to its replacement by faster models on most of the airlines in the United States; (2) the ship was capable of carrying a pay load of 3000 lb. over the required distance; (3) since this airplane had been widely used there would be no difficulty in securing competent personnel or in purchasing spare parts. It was necessary to rebuild the plane for cargo service. The windows were removed and the fuselage was entirely covered. A hatch was cut in the top of the fuselage to receive heavy crane loads and pieces of freight that were too large or too long to go through the rear door. The seats were removed and the interior of the plane was lined with Duralumin sheets. A heavy-duty landing gear was installed and the floor was reinforced. The nearest site for an airport was two miles north of the mine. The necessary grading was done by a small track-type tractor with a wheeled grader, which was brought in overland. Six weeks was required for bring-

Jan 1, 1940

By T. Prof. Ph. D. Egleston

THE importance of having perfectly pure metals has led me to present to the Institute a record of some of the trials that have been made to obtain these metals, and also to show one of the largest specimens of extremely thin metal plate which has ever been made. The malleability of metals varies generally directly with their purity, and hence it is only with very pure metals that thin sheets can be obtained. The competition among different manufacturers has been so great at times as to lead to expensive and apparently useless experiments in obtaining in the first instance very thin sheets, and afterwards very large and thin sheets of metal, apparently with no other purpose than that of being able to say that they had produced the thinnest or the largest thin sheet that had ever been made. These experiments were at first confined exclusively to iron, their object being to show the great dexterity of manipulation, as well as the purity of the metal manufactured. They have since been extended to almost all metals by electrical action, and have gone far beyond the limits of what was possible with purely mechanical means. The processes which have been used are rolling or hammering, electrical deposition in a vacuum, and lastly, electrical deposition on plates, easily soluble in acids. The first and last of these methods have been known and practiced for a very long time, having been used to make thin sheets of almost all the metals. The other is of quite recent application. In the iron manufacture, the strife to produce these thin sheets was commenced in the year 1865, by the Sligo Iron Works writing to a firm in Birmingham, England, on a sheet of iron containing 270 square centimeters, and weighing only 4.469 grams. For some time this was considered to be the thinnest sheet iron that could be made. T. W. Booker & Co., of Cardiff, England, however, produced a few months afterward, a sheet of the same size, weighing only 4.015 grams. This was succeeded by one rolled by Neville and Everitt, of Llannelly, weighing only 3.174 grams. This was followed by one from Hallam, of Swansea, which was 283 square centimeters in size, and weighed but 2.979 grams; and this by one rolled by R. Wil-

Jan 1, 1879

By Willard Jillson

WITHIN the last ten years Kentucky has become celebrated for its low-sulfur bituminous coals. Prior to this time, many investigators had discovered the abundance of this coal but the fact was unknown to the general public until the last extension of Kentucky's mountain railroads was completed. The coals of Kentucky are, broadly, separated into two geographic units-the eastern and the western coal fields. On a basis of their sulfur content these coal fields fall into three units, which are indicated on the accompanying map, by numbers, 1, 2, and 3. The area marked 1, the very southeastern part of the State, shows the lowest sulfur, all coals being averaged. In this field the maximum is 1.04 per cent. and the minimum as low as 0.68 per cent.-both averages and not individual analyses, which would of course show much greater variation. Included in this group are the following counties: Lawrence, 0.87 per cent.; Martin, 0.75 per cent.; Johnson, 0.73 per cent.; Magoffin, 0.S7 per cent.; Floyd, 0.88 per cent.; Pike, 0.68 per cent.; Knott, 1.04 per cent.; Perry, 0.77 per cent.; Letcher, 0.80 per cent.; Leslie, 0.70 per cent.; Harlan, 0.79 per cent.; Knox, 0.86 per cent.; and Bell, 0.92 per cent. The total average sulfur content for these thirteen counties is 0.82 per cent. Bordering the restricted low-sulfur field of eastern Kentucky is the No. 2 belt (slightly darker), which is commonly known as the western border of the eastern coal field. Here the maximum sulfur is 2.91 per cent. and the minimum 1.05 per cent. Again these are averages and not individual analyses. The counties in this group are: Greenup, 2.60 per cent.; Boyd, 1.67 per cent.; Carter, 1.07 per cent.; Morgan, 1.40 per cent.; Wolfe, 1.83 per cent.; Lee, 2.93 per cent.; Breathitt, 1.85. per cent.; Owsley, 1.09 per cent.; Jackson, 1.06 per cent.; Rockcastle, 2.30 per cent.; Clay, 1.09 per cent.; Laurel, 1.08 per cent.; Pulaski, 2.24 per cent.; Whitley, 1.05 per cent.; McCreary, 1.50 per cent.; and Wayne. The sulfur percentage average for this area including fifteen important counties is 1.65 per cent.

Jan 9, 1919

By M. L. Requa

In the fall of 1910, the Nevada Petroleum Co., operating in the Coal-inga field in California, determined to drill a number of wells with rotary tools, in order to prove conclusively the relative value of the rotary as compared with the standard rig. At that time, the rotary was but little known in California and its proposed introduction met with considerable criticism on the part of the operators and quiet opposition among the standard drilling crews. There were few men available who were competent to handle a rotary outfit, and these few had had but little experience in California fields. Machines as then built were much inferior to those now used, being lighter in construction and of a poorer quality of material. The shells encountered at depths between 1,700 and 2,000 ft. seemed to be too hard to permit of successful drilling, and at these depths the rig was changed over to standard tools and by them completed. Because of the heavy depreciation, the time lost in converting from rotary to standard, and the comparatively small profit, it was concluded that unless in the future there was some material improvement in rotary rigs, nothing would be gained by drilling with rotary tools upon this property. Little or no drilling has been done upon the property since that time, but in the meantime a large number of men have been trained in the use of the rotary; in fact, many standard-tool men have abandoned standard drilling and, starting in as roustabouts, have become thoroughly competent rotary operators. The improvements in the machinery have been such as to remove many of the objections and the rotary drilling of to-day is in every way superior to that of 1910. In contrast, a well drilled recently by the Kern Trading & Oil Co., in the east side Coalinga field may be cited. The first 2,500 ft. was drilled in 24 days and it is confidently expected that the water string will be set with a rotary at 3,400 ft.—a record obviously far beyond that made in 1910 by the Nevada Petroleum Co. The records herewith are published with the hope that some one having more recent data will publish them so that comparison may be

Jan 1, 1915

Discussion of the paper of DORSEY HAGER, to be presented at the Colorado meeting, September, 1918, and printed in Bulletin No. 138, June, 191S, pp. 1109 to 1118. WALLACE E. PRATT, Wichita Falls, Tex. (written discussion*).¬Mr. Hager has touched upon interesting problems related to the broad subject with which he has entitled his paper. As to the existence of the important structural feature in the buried Bend series, which Mr. Hager constructs from well-logs, and designates as the "Bend Arch," there seems to be general agreement among a number of observers. Indeed, M. G. Cheney1 and Robt. T. Hill2 have each published structural maps of the Bend Arch that do not differ essentially from the map shown in Mr. Hager's Fig. 1. The reflection, in the overlying, unconformable Cretaceous, of certain folds in the Pennsylvanian, with which the petroleum accumulations has to do, is an important observation on the part of Mr. Hager, since, as he says, much critical territory is covered by Cretaceous, and it is highly desirable that the underlying Pennsylvanian structure be mapped, if possible. If the folds in the Pennsylvanian are of post-Cretaceous age, then it should be possible, in spite of the intervening unconformity, to determine approximately the position of buried folds beneath the Cretaceous overlap. The idea of post-Cretaceous folding would not be out of accord with the suggestion by Carroll H. Wegemann that the folding of the Permian beds in southern Oklahoma was still in progress as late as the Tertiary.3 But most observers have related the folds in the Pennsylvanian and Permian beds at the surface, both in North Texas and southern Oklahoma, to the process of. emergence of the land area at the end of the Permian. It seems more probable that the reflection of Pennsylvanian folds in the unconformable Cretaceous which Mr. Hager observed is due to long continued persistence of stresses which were largely relieved at the close of the Permian, than that the principal period of folding was post-Cre-taceous; this being the case, it seems likely that only folds of greatest intensity in the Pennsylvanian will, be decipherable in the Cretaceous overburden, and that many promising structural features are so concealed by the Cretaceous as to escape detection except by drilling.

Jan 8, 1918

Discussion of the paper of E. L. deGolyer, to be presented at the Colorado meeting, September, 1918, and printed in Bulletin No. 137, May, 1918, pp. 987 to1000. J. A. UDDEN,* Austin, Tex. (written discussiont).-I have read Mr. E. L. deGolyer's paper on The Theory of Volcanic Origin of Salt. Domes, with a great deal of interest. It seems to me a very able summary and discussion of the various theories set forth to account for the origin of our salt domes on the coast. It has always appeared to me that what we need is more observations on the facts involved and I regret very much that so far we have not been able to devote much time to the study of our salt-dome fields on the coast in this State. One feature that I do not find mentioned in Mr. deGolyer's paper is the so-called "cap. rock" overlying the salt. The nature of this rock seems to vary from a coarsely crystalline limestone to a fine-grained limestone containing sand and in which the limestone seems to be intersticially introduced material. We should be prepared to accept, if necessary, "more than one theory. To my mind, the igneous theory and the artesian theory, if I may so call it, may very well both be true. The "squeeze" theory and the artesian .theory may,, it seems tome also, jointly explain the phenomena. Neither the volcanic nor the salt "squeeze" theory explains the presence of the cap rock. The latter certainly does not explain the extensive sulphur deposits which occur in association with the cap rock. Whichever additional theory will be found best to explain the salt-dome structures, when we shall know them better, it seems to me that the theory first advanced by R. T. Hill and later elaborated by G. D. Harris, is not likely to be entirely replaced. Whatever cause has first set into action an upward circulation of gases and liquids in our salt domes, it seems to me that to a gentle circulation of the kind postulated by their theory is to be ascribed the uppermost and the later phenomena in our salt domes on the coast, with which we are most familiar; such as the cap rock, the sulphur, and the gypsum and anhydrite deposits.

Jan 7, 1918

By Ellen H. Richards

It is of importance to analysts to have a ready means of detecting the presence of small quantities of titaninm in iron ores and in certain fluxes and slags. The method given in Elderhorst's Blowpipe Analysis (fusion with potassium hydrogen sulphate) requires considerable practice, in order so to regulate the heat that the titanium oxide shall become soluble. In Brash's Determinative Mineralogy is found a method which, at least in inexperienced hands, has given better results, i. e., fusion of the substance to be tested with sodium carbonate on charcoal in the reducing flame. The solution in hydrochloric acid of the bead thus obtained, boiled with tin or zinc, gives the characteristic violet color; but when the mineral contains less than four per cent. of titanium oxide, long boiling and consequent concentration is necessary. In fact the test would seem to be much less delicate than is generally supposed. In the course of some analyses I quite accidentally found that a peculiar color is given to turmeric paper by solutions of titanium chloride. This color is hard to describe, being modified by the quantity of ferric chloride present in the solution ; but it is neither the orange of zirconia nor the red of' boron. It is rather a dull shade of purple, arid is easily recognized when the paper is dried, although the color fades in a few hours. By this means a solution containing .015 per cent. of titanium oxide can easily be tested. The same solution, treated with tin, required to be concentrated to one-tenth its bulk before a decided color could be obtained. The color given to turmeric paper is intensified after the solution has been treated with tin. This and some other indications show that the best shade of color is given by the titanons chloride rather than by the titanic chloride, and no other salt of titanium than the chloride has been found to give the color. Another peculiar property of titanium salts has come tinder my observation. When titaniferous minerals are soluble in nitric acid, and the solution is subjected to the action of the battery, the soluble titanium salt is converted into the insoluble oxide and appears on the electrode, in some cases, as a white coating; this

Jan 1, 1883