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By Raymond E. Davis

LET'S imagine we are at the Grand L Coulee Dam, where daily 15,000 barrels of low-heat Portland cement and 27,000 tons of processed aggregate in various sizes are mixed to produce 30,000 tons of concrete. Inspect the autographic records which show for each 4-cu-yd. mixer batch of concrete the weights of its constituent materials including its several sizes of aggregate, cement, and water, and which also show the period of mixing and the consistency of the mix. Watch the inspectors sample and test the aggregate for gradation and moisture content of sand, and sample the concrete for homogeneity. Watch the huge buckets deposit the concrete in the forms. It looks too dry to handle, but the concrete vibrators make it melt away. Just enough vibration fully to com- pact the mass, but not enough to produce segregation of the materials; the inspector says when. See the sprinkler system covering all hardening concrete with a spray so that it may not thirst for water. Watch the cleaning of the top of an old lift preparatory to placing a new lift; the sand blasting; the blow-down; the mop-up; the minute inspection.

Jan 1, 1939

By R. D. Parks

DESPITE the handicap of reduced production in many districts, the mining industry in 1938 forged steadily ahead toward solution of its minor technical problems and has of-defected major advances in several fields. In California hydraulic mining for gold, shut down for forty years, will shortly be resumed following revision of restrictive laws. Disposal of hydraulicked ground is to be regulated by settling dams so as not to interfere with agriculture. Gold mining has been aided also by the development of a new high-efficiency dry amalgamator which applies the Ramsay mercury separator to the original de Phily process. Based on the principle that crushed ore will follow a rod into a mercury bath, this simple device is primarily adapted to dry areas and is to be available in small, multiple units suitable

Jan 1, 1939

By Robert S. Williams

NO new ferrous alloys have been produced in the last five or six years that are as outstanding contributions to civilization as were the high-speed steels of the early part of the century or the stainless steels announced at the close of the World War. There have been, however, many developments of major importance having to do either with modifications of existing alloys or with new methods of treatment of older iron or steel alloys. Only a limited number of these new developments can be discussed and their selection does not necessarily imply that these are the most important but merely that they are of general interest rather than perhaps of greater importance in highly specialized fields.

Jan 1, 1939

By Francis A. Thornson

WITHOUT desiring to perpetrate an Irish bull I think we may safely say that the major developments of the year in mineral industry education have taken place outside of the field itself. I refer to the remark- able and-to us of the Education Di- vision-most gratifying growth which is taking place in Institute consciousness regarding its responsibility for the recruitment and adequate training of student personnel and for the successful bridging of the difficult gap between graduation and achievement of professional status. Outstanding in this respect is President Jackling's interest in the students and schools of the mineral industry. Recalling his own hard struggle to ac- quire a technical education, Mr. Jack- ling is evidently anxious to smooth the path for the youngsters of this generation. Witness his splendid gift to the

Jan 1, 1939

By Paul Weir

FOR the first time in 1938, bituminous coal production for the week ending Nov. 19 surpassed that of the corresponding week in 1937, and indexes of industrial activity indicated the possibility that the remaining weeks of 1938 would run ahead of the corresponding weeks of the preceding year. But regardless of this year-end pickup, total production in 1938 was approximately 25 per cent less than in 1937. The estimate of 340 million tons for 1938 places the bituminous industry slightly above the production level of 1933 and approximately 10 per cent above the modem low of 1932. Anthracite production is not subject to the same extent as is bituminous coal to fluctuations arising out of the rate of industrial activity, hence the decline from 1937 has not been so great being approximately 14 per cent under 1937. The estimate for 1938 production is approximately 45 million tons, but this represents the lowest level reached in the last fifty years with the possible exception of several strike years.

Jan 1, 1939

By C. E. MacQuigg

MAN?S desire to harden metal is older than recorded history and obviously would date from the moment when he found his implements were not equal to the demands of service. This need for hardness in metal may be divided roughly into two main classifications: (1 :I need for hardness through- out-for purposes of greater strength or elasticity of the whole implement or member, and (2) need for surface hardness alone. A strong steel needed to transmit stresses or resist de- formation is an example of the first class. In metals only surface- hardened, the chief need is for resistance to wear. Obviously the whole gamut of all uses can be imagined- from the extreme of a simple cantilever supporting a load in space to that of a solidly supported face plate serving to resist wear. It is the in- creasing of wear resistance which I propose to discuss.

Jan 1, 1939

By H. M. Roche

MAGNETITE mining and milling in the Eastern States was sharply curtailed in 1938, production showing a decrease of 36 per cent from 1936 and 57 per cent from 1937. Six mines, one in Pennsylvania, two in New York, and three in New Jersey were in operation, either part or full time, during the year. In recent years ten Eastern magnetite mines have been more or less active but since the World War the market for Eastern ores- has been spotty. The scrapping of Eastern merchant pig iron furnaces, imports of cheaply mined duty-free foreign ore, and high freight cost have been contributing factors.

Jan 1, 1939

By David R. Mitchell

IF you are the owner of a mine, or a mine executive, or just an ordinary miner, and have a son about to go to college, do you urge him to take up mining engineering or do you try to dissuade him from such a course? If you live in the East, or the Middle West and your interest has been in coal rather than metal mining, the chances are that your young hopeful will be urged to do almost anything else rather than follow in father's footsteps.

Jan 1, 1939

By William R. Chedsey

IN the last two years the E.C.P.D. committees having to do with the inspection of engineering schools for possible accrediting have been concerned with the engineering content of some of the mineral industries courses. Originally the discussion arose with regard to engineering geology, or geological engineering, afterward broadening to metallurgical engineering, ceramic engineering, agricultural engineering, and other branches not pertinent to this discussion. Some members of visiting committees took the attitude that they probably would have to accredit these types of training as included in the engineering group if they met the average standard set by the mining schools, though they questioned -whether they were really engineering.

Jan 1, 1939

By Ralph H. Sweetser

OF SPECIAL importance in the design and construction of an iron blast-furnace plant are tile raw materials to be employed. Obviously the iron must come from some ore of that metal, but the many kinds available lead to important differences in plant arrangement, and in the design of furnaces and accessory equipment. For instance, the bulk of the gangue in the ore is subject to wide variation as is that of the ash in the fuel. A gradual increase in the bulk of raw material necessary to produce a ton of pig iron has been noted, but this has been more than offset, so far as costs of operation are concerned, by improvements in the machinery used for handling large quantities of ore. coal limestone, and slag. The mechanization of coal and iron-ore mining. the building of big ore boats and limestone carriers, of ore docks for fast loading and unloading, and the general use of heavy railroad equipment have all contributed to greatly reducing the number of man- hours required to mine, transport, and manufacture the raw materials into a ton of pig iron. This looks like a big saving and it is. If it were not for these big labor saving machines it would be impossible to produce the tonnage of iron and steel that is made each year in this country. On the other hand, the total capital investment necessary to bring down the man-hours per ton of pig iron to a 2.3 hours average at the blast furnace and to a total of only 12 man-hours from ore to metal (see Table 1) is so great that even the present high price of pig iron is probably not far above the true cost of manufacture when all the fixed charges are properly included.

Jan 1, 1939

By W. E. STOKES

SOME extension of flying service to the mining industry occurred in 1938, particularly in Canada, where freighting activity radiated from Edmonton into the new northern mining districts. Again the airplane demonstrated its usefulness in getting new equipment rapidly into the field and in decreasing shutdown time while waiting for repairs. An 18-ton Caterpillar tractor with shovel attachment was disassembled, brought in by plane, and placed in operation at Berens River, Ont., within seven days after its de- livery at Winnipeg. At Central Patricia a mill breakdown required the replacement of a full mill head and trunnion with ball bearings, weighing 2700 lb. The Canadian Airways Junkers, termed the "flying boxcar," was called in from Yellowknife, 1300 mi. away, and the new installation was completed three days later.

Jan 1, 1939

By Daniel C. Jackling

WHAT is written here features some of the things that I would say if I were to de- liver a Presidential address during the Annual Meeting to be held this month in New York. I am aware that custom favors written rather than vocal delivery of such a discourse; and, as this accords exactly with my own preference, I assure readers that they will never be called upon to hear these remarks spoken- anyhow, not by me. My year as President is drawing to a close. As I look back I like to classify and analyze the impressions that have been left with me. It has been a delightful and fascinating experience to me personally; I have appreciated the courtesies and aids, and have been deeply gratified at the honors accorded me. Perhaps the source of greatest satisfaction is the opportunity I have had to sense more about the provinces of this Institute and about the useful functions of the profession that it represents. For 38 years I have been a member. I served two terms as Director-one in 1914-'16 and again in 1927-'29. I have been honored by selection as a Saunders Medalist. I thought I was reasonably familiar with the functions, the ideals, and the activities of the Institute. But the things that I have discerned during the past year have dispelled that conceit. I still think that, a year ago, I was as well informed as most members; but since then I have had the rare privilege of executive service and insight. That has given me a perspective that I feel can be obtained in no other way-as I think the illustrious engineers who have preceded me in office will agree. I wish that I had the power to translate to every member somewhat of the feelings of pride in our organization that a year as President cannot help but instill.

Jan 1, 1939

By B. D. Saklatwalla

FOR the proper understanding of the inclusion of certain elements in this review it seems necessary to state the meaning of "rare metals." Certain elements occur in deposits limited in extent or concentration, so that the extraction of the element in relation to market conditions becomes uneconomical. Others may occur in extensive and rich deposits but the reduction of the metal may be difficult and costly. Both these conditions effect the same result, namely, make the metal rare and costly. As an example of the first kind may be mentioned radium and of the second, calcium.

Jan 1, 1939

By George H. Jones

NO STRANGER phenomenon exists in the American mining industry today than the so-called bootleg anthracite industry in Pennsylvania which now produces probably close to 15 per cent of the total hard coal out- put of the State. Instead of being what - was first thought to be a temporary condition, countenanced because of the desperate condition of some of the miners at the depth of the depression. it is thriving now as never before. Re- ports of it have penetrated all over the world, as exemplified by inquiries concerning it in Durban, South Africa mentioned by John C. Cosgrove in his article in the July MINING AND META LURGY.

Jan 1, 1939

By AIME AIME

ARRANGEMENTS for the Annual Meeting of the Institute were well advanced at the end of December as the following program will show. Heretofore this has been printed separately, but its inclusion in the Annual Review issue of MINING AND METALLURGY will, it is hoped, make it more easily available for reference until the final program is issued, which will be distributed at the meeting. Added details will appear in the February issue. Last year's meeting drew a record crowd of over 2300 which should be exceeded this year. Early reservations at the headquarters hotel, the Waldorf-Astoria, or any other convenient hotel are desirable, as are prompt reservations for the Annual Dinner. No one need worry about too much speechmaking this year, for the honors will be awarded and accepted in a few words instead of a few paragraphs, in seconds rather than minutes.

Jan 1, 1939

By AIME AIME

MECHANIZATION of operations and the development of much more refined preparation practices have been conspicuous achievements in coal-mine engineering in the last two decades. To both, Paul Weir was an outstanding contributor during his seventeen years' service with the Bell & Zoller Coal & Mining Co. and its aliates, the Centralia Coal Co. and the Crescent Mining Co. From 1920 to the end of 1936, when he resigned to go into consulting work in Chicago, he was successively chief engineer, general superintendent, and vice-president of Bell & Zoller. He changed its Zeigler mines from hand to mechanical loading, and planned and built a central mechanical cleaning plant.

Jan 1, 1939

By JESSE L. MAURY

DEVELOPMENT of new gold mines in Canada since the price of that metal was increased in 1932 and 1933 has been of interest and importance to many of us. The day-by-day story has given an impression of aggressive effort and enough good luck so that the spirit of enterprise has been encouraged. It is the purpose of this article to report the results of a statistical appraisal which give emphatic numerical confirmation to this impression, together with certain side lights on the costs of development and equipment of new mines. The data presented have been taken from all readily available published sources up to the close of 1938 and are representative of that year. A. B. Bower did a large part .of the spadework and Weston Thomas offered many helpful suggestions.

Jan 1, 1939

By Donald B. Gillies

TO me a graduating class of engineers constitutes one ' of the finest inspirations I can imagine. You have finished your four- year scholastic career and are starting out in competition with thou- sands of other young men from other universities to make your mark. Be- cause of your training you men are such an essential part of our present- day civilization that a great weight of responsibility rests on your shoulders, especially at this time, for this is an engineering era. Today, it is the engineer who dreams the dreams and makes our civilization better. It's the engineer who carries those dreams into realization and fulfillment. No matter where we go in business and industry, we find- engineers in key positions, charged with great responsibilities.

Jan 1, 1939

By AIME AIME

FRANCIS ANDREW THOMSON was born in London, Dec. 21, 1879, coming to the United States by way of British Columbia where he lived until he matriculated at the Colorado School of Mines. When only sixteen he was inducted into the mining industry as apprentice assayer and millman at the Victoria Metallurgical Works. Following his training at Golden he had more practical mining and milling experience at several properties in the West, and studied a little as well at the Royal School of Mines, in London, and at the Ecole des Mines, in Paris.

Jan 1, 1939

By C. McCulloch

OPEN-PIT mining of coal is relatively a recent innovation; men still active in the industry can trace its development. Re- viewing the growth of operations from the original horse-drawn scrapers, through the various stages of power equipment to the huge strip- ping shovels of today, one also notes changes in the methods of what the coal man calls preparation at the face. We really should not call it face preparation because, in contrast to underground mining, a face does not exist in strip mining. Further, preparation of the coal for market at the loading point has already, in but a few years, become largely of historic interest only and modern mines as well as old mines recently modernized rely almost entirely on separate and elaborate preparation plants to produce marketable coal. This practice was not voluntarily adopted by the producer but was forced upon him by the inadequacy of previous

Jan 1, 1939