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By H. J. LONGMORE

MORE improvements have probably been made in the diamond-drill field in the past decade than were accomplished in the entire prior period since diamond drilling was discovered in 1864 by a French engineer named Leschot. True, machines were improved, and new accessories were adopted from time to time up to 1929, but no radical changes were made. The basic principle instituted during the early years of the industry were still in use in 1929. At that time, practically the only diamonds used were "black diamonds" or "carbon." These came from Brazil through a rather round- about route, and by the time they got to the drilling trade their cost was excessive-$175 per carat and even higher at the peak. Perhaps because of this. or perhaps because of increased competition, the industry sought ways to reduce expenses even in the face of constantly increased labor costs due to higher wages and reduction in hours worked. The solution seemed to rest in two things-use of a cheaper cutting medium to replace the carbon diamond and the development of new machines to drill faster and thus produce more hole per shift of operation.

Jan 1, 1940

By C. M. Fellman

AVAILABLE data for the first nine months of the Year indicate that accident occurrence in metal mining was well on its way to an all-time low for 1939. However, the relatively rapid pickup in mining production in the fall will be likely to boost both accident occurrence and also accident rates. Results of the National Safety Competition for 1938, the fourteenth of its kind conducted by the U. S. Bureau of Mines, were published in August, 1939. W. W. Adams, statistician of the bureau, states that "with 345 mines and quarries competing, more than in any previous year except 1931, the contest revealed low accident rates at many of the enrolled plants and, which is even more remarkable, it revealed 113 mines and quarries at which no lost- time accidents occurred during the con- test year." The National Safety Competition provides a means whereby mines and quarries may engage in active competition to stimulate their safety programs. Companies in the contest can compare their records with those of similar plants operating elsewhere and thereby determine to what extent their safety programs are successful. The Joseph A. Holmes Safety Association gave over 150 awards for safety performance in the mineral industries in 1939 and a remarkable phase of these awards was the considerable number given to individual miners who had worked fifty or more years without sustaining a lost-time accident.

Jan 1, 1940

By E. W. Enqelmann

INCREASED metal consumption throughout the world in the past three years has brought greater activity in the concentrators and mills that treat the ores.' Comparatively low prices have made greater economies necessary, with a continuing search for more efficient flow sheets, equipment, processes, and reagents. Comminution GRINDING has long been too ex- pensive and even any small increment of saving has been eagerly sought. Although not recently new the use of rod mills to cover the gap between intermediate crushing and coarse grinding has made further headway. They eliminate dusting and the closed- circuit operation of fine crushers, either roll or Symons cone, and the rod-mill product is suitable for secondary mills which can be operated with smaller balls and iron liners instead of coarse balls and steel liners. The newer practice is radically different from the older application of rod mills where they at- tempted to use them instead of ball mills for fine grinders. For that purpose they were not well adapted, as they do not have sufficient grinding surface available per cubic foot of mill volume.

Jan 1, 1940

By Percy W. Bidwell

THE statisticians had defeated Germany months before she invaded Poland. With batteries of adding machines they had proved that she was suffering from serious deficiencies in critical food- stuffs and in practically all of the raw materials necessary for the conduct of modern warfare. Their calculations showed that with respect to fats, oils, wool, cotton, hides, petroleum, iron, copper and other metals, the Reich was bound to be at a great disadvantage vis-a-vis the French and British as long as the latter could keep open the lines of sea communication. The conclusion seemed obvious-"Germany can't win." The more cautious of the commentators introduced qualifications as to the length of the war and the tightness of the British and French blockade. They also made a third qualification as to the character of the struggle- whether it was to be a war of attrition or a war of movement. But since the invasion of Norway in April, there is no longer any doubt on this score. It is a war of movement-a war in which fuel, lubricants, and metals are being consumed on a scale never before seen.

Jan 1, 1940

By Nathan C. Rockwood

BASIC mineral commodities may be divided into two general classifications in their market or price characteristics. In one class are commodities sold on a world-wide basis, as gold, silver, nickel, asbestos and petroleum, and in the second are those produced and sold locally. Of course, no precise line of demarcation exists between the two; coal, for instance, belongs more or less in both. If there are enough producers of any commodity to prevent control of production by any one person or group, a free market then exists and the price in a buyer's market is determined by the most favored producer-meaning the producer, with the lowest production cost or the lowest cost of transportation, or both, to the particular market, or place of use. With minerals in the first classification, their high intrinsic value far outweighs the transportation cost and a uniform market price is accepted as an essential element in the economy of distribution. But with common minerals of small. intrinsic value and relatively high transportation costs, economists are reluctant to admit that a uniform price may also be an essential element in distribution.

Jan 1, 1940

By C. L. Clark

EVERY user of steel should ask himself whether or not he is taking full advantage of the discoveries of the steel metallurgists during the last few years, or is merely buying grades that looked to be the best five or ten years ago for various specific purposes and have since proved perfectly satisfactory in his plant. If he has not kept abreast of the times, then it is probable that something better has been developed, or something just as good that costs less. Though this article will have to do with steel for high-temperature applications primarily, marked advances have been made in steels for other purposes as well.

Jan 1, 1940

By W. L. Batt

MODERN war means mechanization, and mechanization means raw materials, especially minerals-and lots of them. Let me recall a few events of recent history-events that constitute mile- stones down the road to the war now blazing on three continents and threatening to spread still farther. In 1932, Japan took Manchuria, largely upon the excuse that she needed raw materials; in 1935, Italy invaded Ethiopia, largely upon the excuse that Mussolini's growing nation needed raw materials-in this case oil; from 1933 to 1935, Germany cried out for a greater share of the world's natural wealth, and since 1938 has invaded or occupied ten other countries, frequently upon the excuse that she needed-and had a right to-more raw materials.

Jan 1, 1940

By AIME AIME

M ODERN metallurgy properly belongs to this century. The great advance made in this science is directly attributable to the discovery of the Roentgen rays. Application of the results of this discovery, together with the more recent corroborating studies in electronic diffraction have definitely and for all time established this science. Metallurgists today speak with familiarity of the atoms of the different metals in terms of their orientation, atomic volumes, lattice structures, dimensional lattice constants distance of nearest approach, and the like. One matter of profound interest, which is quite staggering to the imagination of the human mind, is the enormity of the number of atoms even in a small particle of metal. As an illustration, let us compute the number of atoms in the volume of one cubic centimeter in a single grain of absolutely pure copper. Eighteen and a fraction cubic centimeters equal the volume of one cubic inch.

Jan 1, 1940

By Harold L. Walker

ENGINEERING educators have recently been discussing the advisability of extending the undergraduate curricula to five or six years, and a plan has also been proposed requiring a preliminary period of study in the liberal arts college before admission to the engineering college. Extension of the undergraduate curricula has been suggested as a means of more fully covering the subject matter in the major field of study. Interest in this proposed plan of requiring a preliminary period of study in the liberal arts college has been heightened through a bill recently introduced in the legislature of the State of New York. This plan intends to give a more professional status to engineering, and credit for these additional years of study would be allowed to those engineers applying for professional licensure. As a result of the interest in engineering curricula and due to the impetus given by these proposed plans a general reexamination of curricula has been conducted by a large number of schools with the stated purpose of determining if the present curricula are meeting the aims and scopes of engineering education.

Jan 1, 1940

By J. G. Thompson

IRON, iron everywhere, but hardly a particle of pure unadulterated iron for the metallurgist to use as a base for the protean characteristics that he develops in the alloys of iron-the modern steels. Iron, next to aluminum the most abundant metal in the crust of the earth; one of the oldest metals known to man and serving him as the most indispensable metal in both war and peace; yet man's knowledge of its properties is based on specimens that are not pure and hence probably differ considerably in their properties from the truly pure metal. Purification of iron has brought about startling changes in its electrical and magnetic properties and has modified its behavior in changing its crystal form with temperature, the basis of the heat-treatment of iron. So both the research metallurgist and the metallurgist of the steel plant are intrigued by the possibilities that might unfold were 100 per cent pure iron available in sufficient quantities to determine its properties.

Jan 1, 1940

By AIME AIME

QUALITY and size do not ordinarily go hand in hand, but there is good evidence that both these attributes reached a new peak at the Annual Meeting of the Institute in New York just concluded. Certainly, the total attendance of 2500 was far above any yet attained, as might be expected with the recent rapid growth of Institute member- ship. General comment indicates that the quality of the papers also was notable, though not measurable by so definite a yardstick as attendance. During the meeting 49 technical sessions were held, at which more than 250 formal papers were presented. In addition, there were some thirty special meetings of committees, Divisions, and other Institute groups. In reporting the Annual Meeting eleven years ago the statement was made that "unless the Engineering Societies should build for themselves a new building it is probable that no meeting can be larger," and "the fifth floor, where a buffet lunch is served each day, has reached its full capacity and it seems quite evident that any future development of Institute meetings must be along the lines of quality, not size." Unfortunately the angel to succeed Andrew Carnegie, who financed the building of the present home of the Institute 35 years ago, has not yet ' appeared. Even if some one would merely build another elevator or two in the present building it would help. Fortunately, the modern auditorium of the American Radiator & Standard

Jan 1, 1940

By H. R. Wheeler

CREATION of a "committee on promotion of student interest in coal mining" has an encouraging implication for the coal industry. It is indicative that mining men, both in the field and in the educational centers, realize that the problems of the industry require the best talent available. Young men are being invited into coal on the premise that it needs them, that it offers opportunity for creative work and the realization of their objectives. In initiating a movement which purports to meet the objectives of any young man who spends four or five years of his life in college, the industry does so with a full realization of its obligations.

Jan 1, 1940

By H. V. Flagg

OPERATION of a modern steel plant presents a curious anomaly. Large-scale operations, in which large volumes or heavy weights of materials are involved, are not usually subject to close control or narrow specifications. On the other hand, operations that call for a high degree of precision are usually carried out under carefully controlled conditions with delicate, precise machinery and tools, and production is made secondary to quality. In a modern steel mill both extremes are taken as a matter of course. A strip mill making auto-body sheets must supply its customers with sheets that all come within a tolerance of plus or minus 0.003 in. in gauge at any point from side to side or end to end, and without blemishes either of color or surface. Sheets that were considered par excellence as recently as ten years ago could not even find a market today. Such exacting requirements have made necessary a nicety of control that approaches the watchmaker's art. Notwithstanding this necessity for precision, the scale of operation is stupendous.

Jan 1, 1940

By H. R. Hanley

IN AS MUCH as the interesting changes in the economics of the zinc industry are covered nowhere else in this issue, and they are related to technological progress in the metallurgy of zinc, some reference to prices and production will first be made. The latter part of 1939 is outstanding in the large war demand for metals including zinc, whereas in the first eight months the demand for zinc was subnormal. The cause of the rapid in- crease in demand was the European war and hence the future is problematical. When the year began zinc was in the doldrums, with low prices, and continued thus until August when an advance in price started, reaching 6.5. per pound early in October. (Prime Western, St. Louis.) Rapid changes in the price of any metal are viewed adversely by the metal industry. The persistent low price for zinc of 4 to 49512 for about two years curtailed production and in one instance closed one large plant for a brief period.

Jan 1, 1940

By Donald B. Gillies

WE HAVE come a long way since the time of the old steel master who declared that chemistry would ultimately bring the steel business to ruin. Yet I sometimes doubt whether even now we fully recognize the great debt we owe to the institutions that today are initiating young men into the fascinating mysteries of science and training them in the art of engineering. I am not sure that we recognize the importance of the contribution that the schools of applied science and the technical colleges are making to our industrial economy. That contribution is neither narrow nor restricted. It covers the whole range of industry. Dr. Compton, himself, has shown in his survey of leading American corporations that the engineer is twelve times more likely than the nonengineer to become president, five times more likely to become treasurer, and thirty times more likely to become an officer. So the hand of the engineer not only is all-powerful in the laboratory and in the drafting room but his control is increasing in all departments of management.

Jan 1, 1940

By Oliver Bowles

STRIKING new developments in the field of industrial minerals include the employment of lime, salt, coal, and air for the manufacture of stockings, and the substitution of paper for granite and marble in making tombstones. Certain minerals that have heretofore been regarded as valueless except as museum or laboratory specimens, are now being applied commercially. Serpentine, in forms neither fibrous nor ornamental, massive topaz, pinite, and zoisite are examples. For certain other minerals, notably pyrophyllite, bentonite, vermiculite, and sulphur, extension of established uses into new fields has occurred. Substitution takes a toll in many industries, but producers of industrial minerals as a class have gained more than they have lost in recent years. Encouraging progress has been made in developing at long last a suitable substitute for certain of the uses of mica, the only industrial mineral on the strategic list of commodities established by the War. and Navy Munitions Board. Some of the more important developments in process, equipment, and use .that have come

Jan 1, 1940

By W. A. Eardley

FIFTEEN years ago the world's deepest oil well penetrated the earth about 7300 ft. That depth has now been more than doubled. Why has such deep drilling become necessary and how has it become possible? Three factors have had an important bearing: (1) Depletion of shallow zones, making it necessary to search for deeper producing measures. (2) The perfection of prospecting methods, which have been success- fully used to locate favorable buried structures, many at great depth. (3) Improvement in the quality of steels used for drilling.

Jan 1, 1940

By A. V. De Forest

INSPECTION and test methods of great diversity have been used from the most ancient times to select raw material, control its manufacture, and appraise its finished properties and value. The "miller thumb," expert in grading flour, the vintner's sense of taste, the goldsmith's micro-wear test on a touchstone, the enquiring sniff over the doubtful egg -these are all nondestructive inspection methods, accurate and depend- able, but not readily reduced to numbers in the c.g.s. system. A horse trader inspecting a possible purchase is interested in more than age, size, weight, color. heredity, speed, or drawbar pull which can be reduced to figures. Behavior, temperament, stamina, health-past, present and future---are just as important as the numerically determinate constants.

Jan 1, 1940

By Sidney Snook

FLUORSPAR production is the most important industry in a compact area in southern Illinois and western Kentucky bordering the Ohio River. Producers' activities do not usually figure much in the mining news of the country, so that few know that the last year or so has been an unusually active one. Mine shipments more than doubled in 1939 compared with the poor year 1938. The average price changed but little, though it is now about one-sixth higher than at the beginning of last year. The outbreak of war in Europe a year ago lent an immediate stimulus to the industry, though only about 15 per cent of the domestic consumption is normally imported, thanks to a tariff of $8.40 per ton, equivalent to about 30 per cent ad valorem. Be- cause of the increased production and many expansions and improvements in the mines and plants, the period since the beginning of 1939 has been the most important one for the industry in the last 15 years.

Jan 1, 1940

By C. A. Gibbons

AFTER nine years of extremely de- pressed business, marked mostly A with red ink on the balance sheets of most coal companies and with an increasing internal competitive struggle for diminishing markets, somewhat of a change appeared during 1939. Shipments increased and prices generally firmed, giving the coal industry increasing optimism and encouragement for the future. Specifically, it now appears that bituminous coal production for 1939 will approximate 378,000,000 tons, and anthracite production will approximate 47,500,000 tons, bituminous production being around 14 per cent ahead of 1938 and anthracite production 12 per cent better. The curve on p. 31, showing both bituminous and anthracite production, furnished by the bituminous coal division of the Department of the Interior, shows graphically most of the 1939 monthly production and clearly illustrates the increased production.

Jan 1, 1940