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SMALL things are customarily moulded in two ways (unless they have undercut parts which hold them in the moulds); that is in clay, or with natural or which artificial earthern powder made in halves in either wooden boxes or bronze frames. This also depends on whether the object is larger or smaller. Now if you wish to mould with moist clay, you must grease your relief with oil or pig fat; apply a dusting of charcoal, ashes, or cuttlebone on it; or gild or silver it dry with gold, silver, or tin foil. Then, first make with moist and somewhat firm clay a plate as, thick and large as can conveniently hold your relief, and carefully set the latter halfway into this and let it dry. Then, greasing or dusting it again, make the other half. When both are well dried, take out your relief and at the top make its gates and vents. If plastering is needed, do it. Finally, bake the halves, fit them together, and tie them well, as you wish, using the procedure that I taught you in the discussion of brass. But if one has to make a large quantity of works of one kind, he should for the sake of convenience use the method with powder [120] because it is short and requires less time and expense. Therefore if you wish to do this, you need to have several pairs of bronze frames or wooden boxes, higher than half the relief that you wish to mould, and of convenient length. On a flat board always keep half of one of these frames full of powder that has been slightly moistened for moulding, as I told you, so that by pressing with the ends of the fingers and with the hand it holds together as well as possible. Level it off with a cutting tool and when leveled put a flat board over it and turn it over. Turn it on to a dusting of ashes so that it will not stick, dust it on the other side, and remove the excess by blowing it off Then mould the thing that you wish to mould, pressing it halfway in once or twice, always taking it out and putting it back again. Then the other frame is fitted in its place and filled with earth by pressing and squeezing it carefully. Then it is leveled off on the outside with a sharp tool as you did with the other part, and then one of the parts of the frames is lifted up with the point of a knife or some other tool and,

Jan 1, 1942

By J. L. Whitlock

An attached growth aerobic biological treatment process has been developed at Homestake Mining Co.'s Lead operation which not only oxidizes free and complexed cyanides, including the stable iron complexed cyanides, but also thiocyanate, and the oxidation byproduct ammonia. Through the employment of a mutant strain of bacteria which has been gradually and specifically acclimated to the waste, these potential pollutants are mineralized to relatively harmless sulfates, carbonates, and nitrates. The resultant effluent, through toxicological testing, has been shown compatible with the receiving stream, which serves as a cold water marginal trout fishery.

Jan 1, 1985

By Archer Wheeler

Introduction. THERE are two general methods in use for the production of metallic copper from matte which are worthy of consideration : (1) the Welsh blister process, and (2) the converter process.1 As practically all of the copper produced to-day is made in converters, we will give a brief outline of that process before proceeding with the special subject of this paper. Matte may be roughly defined as a mixture of the sulphides of copper, iron, nickel, silver, etc. In the converter process this is blown up to metallic copper in a modified type of Bessemer converter. The conversion of matte consists mainly in, (1) the removal of sulphur in the form of SO2, and (2) the slagging of the iron. With this brief statement we come to the two subdivisions of the process of converting mattes: Converting with acid linings. Converting with basic linings.

Jan 12, 1913

By Gerhard Derge

A SERIES of studies of the corrosion of tin is under way in the Metals Research Laboratory at the Carnegie Institute of Technology. The complete program includes examination of the corrosion properties of high-purity tin and the changes produced in these properties by the addition of varying amounts of alloying elements. Other studies of this subject have been made recently under the sponsorship of the Inter-national Tin Research and Development Council, but these researches have been confined largely to the weakly acid environments commonly encountered in the canning industry.1 There is little information avail-able regarding the corrosion of tin under alkaline conditions, but such data would be of value, for a large amount of the metal is used under such conditions. The potential measurements to be described were made because they seemed to offer the most rapid method for obtaining a general view of the conditions to be encountered in such service. These experiments will also serve to establish a technique that will be of value in further studies. It must be emphasized that the results reported are those of controlled laboratory experiments and that the conclusions drawn cannot yet be applied to service conditions; rather, they point to the directions in which, more exhaustive experimental work may be clone to best advantage.

Jan 1, 1938

By G. H. Billings

THERE exists an unconfirmed opinion among many ironmasters that the combination of a small quantity of manganese, chromium, titanium, tungsten, aluminium, nickel, and some of the metalloids with iron has a beneficial effect upon the quality. And the impression prevails in some localities that the excellence of steel greatly depends upon the influence of some of these elements. But as the recorded experiments are so meagrely described, and made under such various conditions, the student in search of information upon the subject is somewhat bewildered by the contradiction of the opinions expressed. Observing some interesting phenomena while experimenting with an alloy of iron, copper, and nickel, I was led to determine the effect of some of the metals upon iron as free from contamination by other elements as it is possible to procure in prac¬tice, in order that the result of an alloy of an individual metal with iron might be more closely studied ; for it is almost an impossibility to determine the influence of a small amount of one element upon a metal combined with a large amount of another, and the mere presence of another sometimes makes this difficult. And as most of the experiments recorded upon this subject have been made with iron containing sufficient carbon and other elements to interfere with the effect of that metal the influence of which it was desired to observe, I have endeavored to avoid these sources of error as far as practicable. In determining the specific gravity of the alloys in these ex-

Jan 1, 1877

Discussion of the paper of HAROLD RABLING, presented at the St. Louis meeting, October, 1917, and printed in Bulletin No. 128, August, 1917, pp. 1161 to 1172. A. P. WATT, Mine La Motte, Mo.-The information in Mr. Rabling's paper is of great value to users of the Hancock jig. In the Lead Belt, these jigs treat a larger tonnage than any other type of concentrating machine, and produce tailing of a larger size. This indicates the necessity for logical operation of the Hancock jig. The jigs receive at least 75 per cent. of the total original feed, the other 25 per cent. going to

Jan 1, 1918

Jan 1, 1939

By Franklin Bache

It is appropriate to the place of meeting, and of interest to those members of the Institute whose attention has been more or less directed to Virginia during the past eleven years, to know the result of recent developments of the Virginia coal-field. While, during the late " boom," the attention of the industrial pioneers of Virginia was mainly directed to iron-ore deposits and manufacture, it is safe to say that the coal to which, at that time, comparatively little attention was turned, and which did not directly foster a growth of " boom " towns, will prove the most reliable source of mineral wealth in the State. At the time of the last Virginia meeting of the Institute, held at Roanoke, in 1883, the Wise county coal-field was untouched by a railroad, and its economic existence was scarcely considered. Although, in the meantime, a number of reconnaissances had been made, and a fair estimate of the value of the field formed, it was not until 1891, when the Norfolk and Western and the Louisville and Nashville railroads, respectively, completed their Clinch Valley and Norton extensions to a junction at Norton, Wise county, that any development took place, and not until 1892 were shipments of any importance made. The coal-measures of Virginia are confined to the seven counties of Buchanan, Tazewell, Dickenson, Russell, Scott, Wise, and Lee,

Jan 1, 1895

At the University Club, New York, Jan. 23, Chairman George E. Hale and other officers of the National Research Council, gave a dinner to officers of the national engineering and other societies. About thirty persons were present, including officers of the National Research Council, the four Founder Societies, American Society for Testing Materials, Society of Automotive Engineers, Inc., Illuminating Engineering Society, United Engineering Society, and Engineering Foundation. Letters were received from the Western Society of Engineers, which also had been invited. Gano Dunn, vice-chairman of National Research Council, was toastmaster. The proposed permanent organization of the National Research Council and possible methods of connection with the national engineering societies, either directly or through Engineering Foundation, were outlined. It was suggested that not only the four Founder Societies be represented in the Engineering Division of National Research Council, but also that the other national engineering societies be admitted to membership. It was proposed that the Engineering Division should have a chairman who should be an engineer of wide reputation and of the highest professional attainments who should devote his whole time to the establishment and development of the Division. Methods of organizing industrial research were discussed. At a subsequent meeting of the National Research Council, an invitation was issued to each of the national societies to form a research committee encouraging that committee to become active in the promotion of research within its respective field. Due recognition is to be given each committee in the general organization of the National Research Council. Dr. H. M. Howe, in a very interesting and comprehensive address, told of much important work that had been clone by the various sections of the Research Council, as that of mechanical engineering in developing the often rather nebulous devices for helping win the war and putting them in such form that they could be of direct use to the military service. The section on metallurgy, till lately under Bradley Stoughton and now under G. H. Clevenger, did much valuable work in the improvement of helmets and body armor and made very extensive ballistic tests with refractory steels for this purpose. Important work was done in investigating the fatigue of metals and results of great moment were achieved. The committee on ferro-alloys, under J. E. Johnson, Jr., did important work in effecting economy of manganese in steel manufacture with a view to reducing the necessity for importation of manganese ore, thus releasing ships for other purposes. , The section on electric welding has accomplished valuable results in the development of electric welding for ships, a new branch of industry of very great promise.

Jan 3, 1919

Jan 1, 1939

By Erwin S. Sperry

Brass or bronze chips, grindings, buftings, washings, and miscellaneous scrap metal sooner or later find their way into the hands of the so-called metal-smelter or " refiner," whose refining or smelting operation consists simply in melting the material, adding the requisite amounts of other metals, and then casting it in the form of ingots, which are afterwards sold

Jan 1, 1899

By ALFRED D. FLINN

ENGINEERING COUNCIL has passed, not out, but upward! Therefore, its recent wake was conducted by itself as a joyful occasion somewhat in advance of its official demise. Council held its last meeting in Washington, Dec. 16, 1920. Business was transacted with dignified gravity in the forenoon. During the afternoon calls were made upon the chiefs of technical bureaus of the Government: the Chief of Engineers, U. S. Army; Chief of Yards and Docks of the Navy Department; Director of U. S. Reclamation Service; Director of U. S. Geological Survey; Director of Bureau of Mines. The Council pronounced them, each and all, able men and true. But what of the evening? Well, there was a dinner at the Washington Hotel. Twenty-six men gathered around a flower-strewn table-not a casket. As guests, there graced the festive board the hosts of the afternoon calls, and a number of members of the new American Engineering Council. The body about to be apotheosized-otherwise known as Engineering Council-was both jocular and reminiscent. Rewards were bestowed and appreciations expressed. To the man who had for three long years borne the burden of chairmanship and whose financial recklessness made possible the Washington office and the movement for a National Public Works Department, the following "note," duly engrossed and signed, was given, accompanied by "The Song of the Council Crew."

Jan 1, 1921

By R. W. Hunt

One of the serious and important economic administrative problems facing American railway authorities today is that of their rails, and it is one to which much thought is being given…

Jan 1, 1915

Jan 1, 1931

Jan 1, 1932

Jan 1, 1949

By C. M. Smith

DELEGATES from 26 Local Sections and- Divisions of the Institute had three stimulating sessions during the Annual Meeting, a few topics still remaining to be discussed after the two Monday sessions.. The final session was held on Thursday morning. An abstract of the discussion will be transmitted to each delegate present. The topics included: Student relations. Section operation, membership, employment, MINING AND METALLURGY, a new nonmetallic minerals Division. licensing of engineers, and increased allotments of money to Local Sections. Some of the Sections felt that the present limit of $250 allotted to them - from the national treasury was insufficient to carry on their activities, and that this maximum should he increased. A resolution to this effect was passed for transmission to the Board of Directors.

Jan 1, 1935

By J. E. Brantly

In October 1939, a drilling program was commenced on the Atlantic seaboard of Brazil, with three steam rotary rigs of medium capacity. One of these was assigned to the State of Alagbas and the other two to the State of Bahia. During the remaining few months of 1939 and during the year 1940, some eight wells were drilled, two in Alagbas and six in Bahia. Two small producers were found in the latter state. In early 1941 three medium-weight Diesel rigs were added to the equipment, thus permitting the drilling of some 15 wells during the year 1941. The two small producers found in 1940 in the State of Rahia were near the city of Silo Salvador. In 1941 three additional small wells were brought in, in the same area, and a further producer on an isolated structure some 75 km. to the northwest of this production. No commercial production has been found in the State of Alagbas. Approximately 26 wells have been drilled or are drilling, six of which are producers— five in one area and one in another. The program for 1942 calls for the development of the two areas in which wells have been found and also the drilling of several wildcat structures located either by geophysics or surface geology. All production in the area of the several producing wells is somewhat less than 2000 ft. and in the other area about 3800 ft. The area of the several wells is known as the Lobato field, and is practically within the city limits of Sao Salvador. The area 75 km. northwest of the city will be known as the Candeias field.

Jan 1, 1942

By J. E. Brantly

In October 1939, a drilling program was commenced on the Atlantic seaboard of Brazil, with three steam rotary rigs of medium capacity. One of these was assigned to the State of Alagbas and the other two to the State of Bahia. During the remaining few months of 1939 and during the year 1940, some eight wells were drilled, two in Alagbas and six in Bahia. Two small producers were found in the latter state. In early 1941 three medium-weight Diesel rigs were added to the equipment, thus permitting the drilling of some 15 wells during the year 1941. The two small producers found in 1940 in the State of Rahia were near the city of Silo Salvador. In 1941 three additional small wells were brought in, in the same area, and a further producer on an isolated structure some 75 km. to the northwest of this production. No commercial production has been found in the State of Alagbas. Approximately 26 wells have been drilled or are drilling, six of which are producers— five in one area and one in another. The program for 1942 calls for the development of the two areas in which wells have been found and also the drilling of several wildcat structures located either by geophysics or surface geology. All production in the area of the several producing wells is somewhat less than 2000 ft. and in the other area about 3800 ft. The area of the several wells is known as the Lobato field, and is practically within the city limits of Sao Salvador. The area 75 km. northwest of the city will be known as the Candeias field.

Jan 1, 1942

By B. Prof. Silliman

THE occurrence of diamonds of some size in the gold-fields of California is by no means uncommon, and was noticed by me in a communication, to the California Academy of Science in 1867, when specimens of this gem, from at least five different localities, were exhibited. I then suggested that a more attentive examination of the heavy sands left in the sluices of hydraulic washings would in all probability detect diamonds, mingled with other rare species not commonly believed to have occurred in these sands. Mr. George A. Treadwell, of San Francisco, has lately sent me a small package of these sands, collected by him from the sluices of the "Spring Valley Gravel Mining Claim," Cherokee, Butte County, California. A microscopic examination shows these sands to abound in beautiful colorless zircons (hyacinths), of the form well known in the hyacinths of Expailly (France), associated with crystals of topaz, quartz in fragments, rounded grains 'of chromic and titanic iron, and

Jan 1, 1873