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By H. O. Hofman

The sudden decease, April 1, 1910, in Chicago, of Dr. Franklin R. Carpenter was a shock to his many friends. He died in his sixty-second year, of heart paralysis. To most fellow-members of the Institute who have followed the progress of the last twenty-five years in the mining and treatment of non-ferrous ores, the work of Dr. Carpenter in that line is familiar; but very few, even of those who knew hinl well in the later years, are acquainted with his earlier struggles to satisfy an inborn hunger for knowledge. The story of his life resembles that of the pioneer who opens up new country; overcoming hardships with indomitable courage, meeting doubts and difficulties with an alert and open mind, and exercising in the face of reverses an unconquerable perseverance. It seems appropriate to place on record in the Transactions a brief outline of the life and work of this eminent engineer. During the past 15 years of his life Dr. Carpenter was much interested in genealogy. In the pursuit of this study as an avocation, he traced his own ancestry to the time when ((Hugh," called "le Charpentier" on account of the dexterity with which he had swung his battle-axe as a crusader, settled in Sussex on lands received from William the Conqueror. The Carpenters came to this country with William Penn. A prominent member of the family was Joshua Carpenter, the founder of Christ Church, Philadelphia. Dr. Carpenter's branch of the family moved from Pennsylvania into that part of Virginia which is now West Virginia, where his grandfather settled in Harrison county, while the grand-uncle went further west, and built the first iron-furnace at Hanging Rock, Lawrence county, Ohio. In fact, since early times, the Carpenters appear to have been iron-masters. Franklin R. Carpenter mas born, Nov. 5, 1848, in Parkers-

Jan 1, 1911

By Harold Rose

THE peak of production from the Appalachian natural gas field was apparently reached about 10 years ago, and the annual production from Pennsylvania, West. Virginia and Ohio has now dropped to about two-thirds of the amounts obtained in 1916-and 1917. This falling off in production has occurred in spite of vigorous efforts and large expenditures by producing companies to maintain or increase their output. The greatly increased costs of development and handling are reflected in the present average value of natural gas at the point of consumption, which value in the three states referred to, has more than doubled in the past 10 years. While it is true that the natural gas production of the United States has increased during recent years, this increase has come from southwestern states, particularly from Oklahoma, California, Louisiana and Texas, which states are now leaders in the production of this valuable but fleeting resource. Pennsylvania, originally the leading state in natural gas production, occupies sixth place in the latest (1924) U. S. Bureau of Mines statistics. West Virginia, which held first place for 15 years, has dropped to third rank, and Ohio is the seventh state in the order of natural gas production. Domestic and industrial demands for gas are constantly increasing everywhere in the United States. These growing demands have accentuated the difficulties in the localities with depleted natural gas supplies, and serious shortages have already occurred during winter months in the Pittsburgh district. Some relief has been obtained by placing restrictions on the industrial use of natural gas, and by, increasing the price (which tends to reduce consumption). Yet these are but temporary expedients for checking gas consumption, which fail to solve the problem of adequate future supplies of gas.

Jan 10, 1926

ALTHOUGH the first colonists in the area that is now the United States, whether Spanish, French or English in nationality, were usually keenly interested in the possibilities of mineral wealth, it is a curious and interesting fact that none of them happened upon the mineral deposits that eventually were to make this the greatest mineral-producing country; up to 1800 it would probably have been rated as rather poor in minerals. Spanish explorers traversed the southeastern United States with- out finding the Appalachian gold deposits that aroused so much interest in the early nineteenth century; Coronado sought in vain for the seven golden cities of Cibola; and the important gold deposits of California were not discovered until the political sovereignty of the region had passed from Mexico, which had held it for three centuries. The French also held Canada for nearly two centuries (and the British for another century) without finding the mineral deposits in Ontario and Quebec that now are so important. Though they knew of the copper of the Keweenaw peninsula, the lead ores of Wisconsin and Missouri, and the coal of Illinois in the seventeenth century, these deposits were all too remote for exploitation. In the area held by Great Britain, iron smelting was planned at Jamestown as early as 1619 and was actually begun at Lynn, Mass., in 1643. The industry grew slowly, at first, but had reached considerable importance before the Revolution. Commercial bituminous coal mining began about 1750 in Virginia but anthracite mining in Pennsylvania was not started until 1800. As a result there was naturally little interest in the technical aspects of mineral production here before 1800 by any except the few people who were actually engaged in it. Students of natural science were much interested in minerals, however. The activities of those who rank as geologists are so thoroughly covered in

Jan 1, 1941

By J. P. Witherow

The Clapp and Griffiths steel-process may be considered a pneumatic system, similar to the Bessemer, with the difference that the converter is fixed or non-tilting, and that the blast is introduced around the lower section of the converter instead of through its bottom. Mr. Griffiths was engineer-in-chief of the Gilchrist & Thomas basic dephosphorizing process during all the time those gentlemen were experimenting and working up their system, as Mr. G. communicated to me. After separating from these gentlemen, he began developing the present Clapp and Griffiths type of converter. Dr. Clapp, of Nantyglow, Monmouthshire, was a prominent physician in a large iron district. Previous to his association with Mr. Griffiths, he took out some patents on a process of his own for the manufacture of steel, which patents stood in Mr. Griffiths' way; hence the consolidation. Early in the summer of 1883, my attention was called to the experiments of Messrs. Clapp & Griffiths in Great Britain by a friend who had just returned from England. Later in that summer I went to Newport, on the border of Wales, where I met Messrs. Clapp and Griffiths and their friends. After visiting two small converters of their type which were in operation at different works, and spending a few days in the iron-districts of Wales, I went to London, where I met my friend Henry W. Oliver, Jr., who had already heard of the new steel-process. We decided to revisit Wales and examine more fully the process, more especially that Mr. Oliver might have the opportunity of coming practically in contact with the men and die process himself, so that his judgment might not be influenced by my sanguine feelings. On

Jan 1, 1885

By Donald F. Taylor

TANTALUM and columbium are newcomers in the world of metals. Many of the metals described in this volume had been known and used for centuries before either tantalum or columbium was known to exist. The scarcity of the ores and the comparative difficulty of extraction delayed their technology until specialized methods of processing could be developed. HISTORY Early in the nineteenth century, 1801, Hatchett discovered a new oxide, which he called columbium oxide, and a year later, Ekeberg announced that he had found a new element, which he named tantalum. The preparation of the metal tantalum in impure form was first announced by Berzelius in 1824, but the actual production of ductile metal did not occur until 1903, when von Bolton, of Siemens and Halske, developed a process for the production of tantalum pure enough to be drawn into electric-lamp filament wire. The use of tantalum as a filament wire began to decline when ductile tungsten was introduced in 1909. In 1921, C. W. sake, of Fansteel Metallurgical Corporation, produced the first ingot of tantalum metal in America. The first ingot of columbium was produced in 1927 in the laboratory of the same company. There are several good reasons why tantalum and columbium are often mentioned together. They occur together in their important minerals, are similar in many of their properties, and are

Jan 1, 1953

By AIME

To be born in the East, reared and educated in the West, to do graduate work in Germany, leading to the doctorate in metallurgy, and to wind up-for the time being at least-in the Middle West as head of one of the outstanding mining and engineering schools of the country, is a unique career. Curtis Laws Wilson, dean (and in most respects, president) of Missouri School of Mines and Metallurgy at Rolla, is a native of Baltimore. He came to Anaconda in 1918 and in due course was graduated from Montana School of Mines, with an exceptional record. In 1921, after experience in metallurgical research at Anaconda, he became instructor in metallurgy at his alma mater. Because of his ability as a teacher, he rose rapidly to head of the department after special work at Columbia in 1923-24. In 1927, Wilson was granted leave of absence to study physical metallurgy under the great Tammen at Goettingen, and returned with his doctorate to his work at Montana School of Mines. His major metallurgical interest was then in age-hardening of copper alloys. Also after his return to Montana Mines, Wilson started

Jan 1, 1948

By Lytle Brown, Thomas C. Meadows

The rock now known to almost every Middle Tennessee farmer as " phosphate," was but recently recognized as such. The existence of a stratum of black siliceous rock in the hills surrounding the Nashville Basin has been known for many years to Dr. Safford, the State geologist. Nothing about it, however, would lead to the conclusion that it contains a considerable amount of bone phosphate of lime. The only feature that might attract attention is its very dark color; and since it occurs near the " black slate," one would naturally infer nothing more of interest to be connected with that feature than that this rock and the " black slate " derived their carbonaceous matter from a common source. Many of the country people have mistaken it for coal, or for an indication of coal; this impression being strengthened by the fact that, when a piece of the rock was thrown into a blacksmith's forge, a slight combustion was observed. As will be more fully explained, the phosphate-rock is of two kinds: (a) loose or separate boulders, occurring in a stratum of clay or blue shale; and (6) solid rock occurring in a continuous stratum. The boulders have been known for a long time as "balls," "kidneys," " stink-stones," etc. ; and as early as 1887, an analysis made under the direction of Dr. Safford, at Vanderbilt University, showed one of these boulders to contain 64 per cent. of bone-phosphate of lime. This information awakened no great interest in the matter, for the probable reason that at the same time it was known, or supposed to be known, that the boulder-beds were of limited extent as

Jan 1, 1895

For the past several years the policy of a large section of our mining industry in relation to our present bureaucratic form of government has become increasingly amusing, if not a little disgusting. In the past, mining men have always featured themselves the self-announced champions of free enterprise, and, generally, this conviction, was substantiated by their deeds. In recent years, however, a large group of the industry, while still expounding, from the front porch, the principles of free enterprise and a sound economy based upon the law of supply and demand, have gone around to the back door with palm extended, to join labor, farmers, bureaucrats, and other pressure groups to get their share of the take. The procurement of subsidies, bonuses, increased metal prices, and government assistance in a multitude of forms seems to have obscured from their thinking the welfare of the country as a whole and the sounder economic principles of a balanced budget and lower taxes. At the recent Colorado Mining Association convention in Denver, I. was alarmed to see just how far this specialinterest type of thinking has progressed within the mining industry. Government assistance to mining. was generally considered inadequate, and a flat bonus for any new mineral discovery was proposed. It was disquieting, too, to learn how far the federal alphabet agencies have entered into the mining industry and of the thousands of highly paid technical. men on the federal payroll required to man these numerous overlapping agencies and bureaus. Now all this is very fine, and some aspects of the federal give-away program can be very appealing to the unsuspecting in the mining industry as they have been to those in other groups. Some of these expensive programs may bring about a few dividends or even several new mines. But to this whole line of pump-priming reasoning there is one big disastrous fallacy.

Jan 1, 1952

H ORACE VAUGHN WINCHELL was born at Galesburg, Michigan, Nov. 1, 1865, and died at Los Angeles, California, on July 28th of this year, at the age of fifty-seven. Mr. Winchell was one of the conspicuous geologists of his time. It may fairly be said that he was a geologist born and reared. His father, N. H. Winchell, was professor of geology at the University of Minnesota; his uncle, Alexander Winchell, was professor of geology at the University of Michigan. Under both of them Horace studied, graduat-ing at the University of Michigan in 1889. Mr. Winchell at once began that active life in the field which he followed for 34 years and until his death. The first years of his professional life were largely spent in the study of the iron ranges of Min-nesota. In 1898, he re-moved to Butte and became geologist in charge of the geological depart-ment of the Anaconda Copper Mining Co. and allied companies. There he remained for eight years. This period covered the trying days of the mining controversies be-tween the Anaconda and associated companies and the Heinze interests, and it fell to Mr. Winchell to direct the geological studies and development in connec-tion with that litigation. Recognizing the importance of careful geological study in the practical operation of mines, he organized and developed the splendid geological department of the Anaconda Copper Mining Co. This was one of his greatest contributions to the mining industry. Probably no mining company has attached the impor-tance to geological study and continuity of geological mapping in connection with mining operations that the Anaconda company has. It has given broad authority to its geological department and the development of its mines is under the direction of its geologists. The broad vision of Mr. Winchell was responsible for the adoption of this policy, one which is being profitably employed by many other organizations.

Jan 9, 1923

By William H. Kobbé

THE CHAIRMAN (M. L. REQUA, San Francisco, Cal.).-We have had in California a great deal of trouble from the breaking. off and collapsing of well casings from shifting sand, and it is quite true with us as indicated in the paper, that no casing has been found sufficiently strong to withstand that. I know of wells in which casing that has not been in the hole over 2 or 3 days has collapsed and when that casing has, been pulled out it has been just as flat as your hand. I am also familiar with swelling bed rock in the gold drift mining ground of California. It does swell and keeps on swelling and never seems to stop. Just as long as tunnels are kept open in that kind of material there has to be a gang going through the tunnel constantly cutting out and easing up. They have put in timbers 24 in. in diameter in an effort to hold that kind of ground and it has always filled. The only way to succeed is to keep a gang of men busy all the time cutting out and easing down as it squeezes in. C. NARAMORE, Washington, D. C.-My experience has been very similar to yours in, the same field in the matter of breaking off of casing. I had charge of one well, in which I put in reënforced casing, anchored it in place and got 1 day's production, 150 bbl., out of it. The following morning my lease foreman telephoned that it had broken off. I thought at that time we would have more evidence, so I drove out to the well without ordering a new shoe joint. It had been customary to merely start from town with a new shoe joint, pull the pipe, take off the crooked bottom joint, start the casing back and sometimes never touch any iron (lost casing)- when redrilling the well. Where the flattened joints went

Jan 4, 1917

R. M. Raymond, New York, N. Y.—The filling and drawing down of the overhead material was done at considerable depth, which is not the usual method in which it starts at the surface.. R. J. Mechin.— It is a little more than 1000 ft. at El Bordo. The vein above had been caved practically to the surface and some of the ore had been excavated, using underhand and overhand square-set methods. This was far enough away from the shaft to prevent any bad effects. When the sill floor was taken out, to insure the old cave material following down well, we put chutes in the square sets for several weeks until we were sure that the material from above was moving down; on each level above, several crosscuts were driven into the old fill by which we could see the material coming down and thus be sure it was following the first. We had to dynamite it very little because it was dry and dusty. The only trouble was that timber starting from the old square sets would get across the chute and hang up. R.. M. Raymond.—HOW many floors did you operate at once? R.. J. Mechin.—We would operate one floor through the whole length and prepare for the second. F. W. SperR, Houghton, Mich.—Could you have worked it in steps? R.. J. Mechin.—Yes; but working it all on one floor was much better for ventilation. The passage between steps would tend to become heavy and blocked and, as the passages from the mining floor down are usually filled with ore, there would be no way for the air to pass up. By means of doors and fans, air was driven to the extreme end of the orebody through the stope and up the other end; but it could have been worked in steps. F. W. SpeRR.—D the following-up material ever become so heavy that you could see weight on the caps before you had to take out the posts?

Jan 1, 1927

This study of engineering education arose out of the action of a joint committee on engineering education, representing the principal engineering societies. The committee had gathered so much material that it decided the work could best be carried out by some one trained in applied' science, who would devote his entire attention to the study.. The Carnegie Foundation therefore asked Prof. Charles R. Mann, of the University of Chicago, to undertake the work. After making a thorough study Prof. Mann has made a most comprehensive report. In it he says: The engineering schools of the United States began their work upon a definite teaching plan and one that had at least pedagogic consistency. But during the past half century the course of study has been overlaid with many special studies intended to enable the student to deal with the constantly growing applications of science to the industries. As a result, the load upon the student has become so heavy that there is a feeling that the students fail to gain a satisfactory grounding in the fundamental sciences and do not fulfil the expectations of engineers in d manufacturers in dealing with the practical problems with which they are confronted on leaving school. At present 60 per cent. of those who enter the schools fail to graduate, still many of them persist in engineering and make a success of it. It is evident, therefore, that the present systems of admission are not satisfactory. If a group of schools will take up the careful study of their entrance systems and experiment with objective tests and records of the students' youthful interests and achievements, the percentage of elimination can be reduced to at least a fourth of its present size, with an enormous saving of time, energy, and money for both student and school. The number of required credit hours per week should be less than eighteen, preferably sixteen. The few experiments that have been made indicate that college students do their best work when not more than five subjects are studied at a given time.

Jan 1, 1919

By D. L. Johnson

Only general treatment of a subject of such scope can be given in a short paper, therefore, except in a few instances, statistics and descriptions of specific installations are omitted. The earlier applications of electricity to the production of petroleum in the Mid-Continent field were widely separated chonologically, each holding a special interest, and each contributing greatly to the present development. Electric Pumping One of the first installations of electric pumping was on a lease near Jenks, Okla., in the Arkansas River bed, where a difficult problem was solved by the use of motors. The Arkansas River had frequent flood periods which interfered seriously with the use of jacks and pull rods. Small piers were built with old casing used as piling, and upon these were set small jacks driven by 3-hp. squirrel-cage motors. The starting switches were located on a bank and the power was furnished by a small generator, which was driven by an oil country gas engine. This installation was made in 1913 and is, I believe, still in satisfactory operation. In 1914, the Cushing field came in and the Hill Oil & Gas Co. electrified its Shamrock property, using eight-pole Star Delta motors, rated at 10 to 30 hp. and belted through countershafts to the band wheel. Power was furnished by a small generating plant consisting of two 135-kw. machines, gas-engine driven. Considerable difficulty was experienced in the early operation of this station because of low voltage. It is characteristic of small alternating-current generators that voltage regulation will be poor with widely fluctuating loads. This field had three producing sands, and a number of wells were redrilled with the motors, and this, together with a great deal of swabbing, was responsible for the bad load conditions. However, when the wells had settled down to steady operation, the electric equipment functioned satisfactorily, and continued in use as installed until a few years ago when the present owners contracted for service from a central-station company and shut

Jan 1, 1928

One of the engineering proposals in the last Congress which was of interest to engineers was the soldiers' land settlement plan proposed by Secretary Lane, under which returned soldiers, sailors and marines would be employed on construction work in the reclamation of swamp and arid lands and would thereafter be given preference in the selection and settlement of those lands. This bill failed in the fillibuster at the end of the session. It is likely that some sort of a plan for soldiers' settlement will come before the next Congress. A new bill has been written up for introduction at the next session which proposes an "infiltration method" of buying improved farms in established communities for' the soldiers' settlement purpose, under the authority and direction of the Farm Loan Board. The contrast of this bill to the one recommended by Secretary Lane is of vital importance to engineers at this time; first, because of the broad engineering improvement program that the latter bill proposes as against no engineering improvement under the infiltration plan; secondly, the community settlement plan of Secretary Lane means improvement of waste lands requiring much engineering work.

Jan 7, 1919

By M. W. Strong

The technique of handling drilling muds varies somewhat, partly because of personal factors but mainly because of differences in formation, the type of problems, and the general drilling conditions in different localities. The much greater depths to which bore holes are now carried have made necessary closer attention to and great modifications of all aspects of drilling-mud technique. Increased depth means smaller hole, smaller drill pipe, smaller clearances, higher pumping pressures, higher differential pressures between shows and the mud column, less accurate control of the weight of the mud column, delayed receipt of formation data, and poorer samples. It means longer delays and greater hazards in rectifying mistakes or dealing with accidental occurrences. Equipment on a larger scale is necessary and more pains must be taken with layout. Lastly, the budget costs of raw materials have risen to high figures and economy of time and of direct monetary expenditure have come to mean much more than formerly. A mud laboratory is now part of the essential establishment of a modern oil field and to it current problems can be submitted for the most thorough investigation. The detailed chemical properties of all materials purchased or quarried have to be investigated. Detailed data on the physical properties have to be ascertained and research on improvement of material and its most efficient use has to be carried out. In this paper will be discussed the main mud problems of Iran, some of which are peculiar to local conditions while others are of the general type common to all workers in this subject. Underground Conditions In deep wells in Iran the normal overburden may consist of: (1) up to several thousand feet of marls with interbedded sandstones and limestones of varying porosity and permeability; (2) beneath this a chemical series of rock salt and anhydrites, containing various marls and thin limestones,

Jan 1, 1939

By M. W. Strong

The technique of handling drilling muds varies somewhat, partly because of personal factors but mainly because of differences in formation, the type of problems, and the general drilling conditions in different localities. The much greater depths to which bore holes are now carried have made necessary closer attention to and great modifications of all aspects of drilling-mud technique. Increased depth means smaller hole, smaller drill pipe, smaller clearances, higher pumping pressures, higher differential pressures between shows and the mud column, less accurate control of the weight of the mud column, delayed receipt of formation data, and poorer samples. It means longer delays and greater hazards in rectifying mistakes or dealing with accidental occurrences. Equipment on a larger scale is necessary and more pains must be taken with layout. Lastly, the budget costs of raw materials have risen to high figures and economy of time and of direct monetary expenditure have come to mean much more than formerly. A mud laboratory is now part of the essential establishment of a modern oil field and to it current problems can be submitted for the most thorough investigation. The detailed chemical properties of all materials purchased or quarried have to be investigated. Detailed data on the physical properties have to be ascertained and research on improvement of material and its most efficient use has to be carried out. In this paper will be discussed the main mud problems of Iran, some of which are peculiar to local conditions while others are of the general type common to all workers in this subject. Underground Conditions In deep wells in Iran the normal overburden may consist of: (1) up to several thousand feet of marls with interbedded sandstones and limestones of varying porosity and permeability; (2) beneath this a chemical series of rock salt and anhydrites, containing various marls and thin limestones,

Jan 1, 1939

By C. W. Tomlinson

INTRODUCTORY THE analyses which have been made by the writer according to the method described below were made as part of Professor Withey's investigation of the concrete aggregates' of Wisconsin, in the hope of throwing light on the extent and nature of the influence of the mineralogical constitution of aggregates upon the properties of the concrete, and mortar made from them. This method was found most satisfactory after four weeks of experiment and modification. It attains an accuracy quite sufficient for the purpose of the analysis, and is fairly rapid. Mineralogical analyses may be thus made at a cost considerably less than that of chemical analyses of a similar degree of completeness. The results obtained by this method should not vary in any item by more than 1 per cent. of the total weight of the sample, and may be made very much better than this by the exercise of greater care in the microscopic counting (see below). The accuracy of the hand sorting 'is of course dependent upon the experience and carefulness of the analyst. . After a month's practice, the writer was enabled to turn out these analyses at the rate of four in 33 hr. of working time. It was found most economical to handle four samples at once. The samples analyzed weighed froth 290 to 340 g. each. The same method could be applied to larger or to smaller samples, within reason able limits. The following list covers the necessary apparatus and equipment: 1 good balance capable of weighing accurately to tenths (or, better, hundredths) of a gram, and of handling quantities up to 200 g. in weight. 1 Westphal balance, registering densities to two or three decimal places. 1 Meker or Bunsen burner, and gas supply. 1 nest of sieves, 10, 20, 40, and 100 meshes to the inch.

Jan 5, 1915

By E. Lancaster-Jones

THE gravity magnitudes obtained by means of observations with the Eötvös balance in the field are necessarily resultant or total effects due to all abnormalities of mass distribution, including even the effects due to the ellipticity and rotational motion of the whole earth. Since the object of the survey is to isolate the effects which arise solely from some particular subterranean feature, and to deduce therefrom the configuration and extent of this feature, the first step is to eliminate from the observed effects all those due to "disturbing" (i, e., unwanted) features, whether above or below the surface of the ground. The disturbing features have different characteristics, according to their situation relative to the center of the balance and to the horizontal plane through the foot of the balance, or station point; this diversity was recognized by Eötvös, who divided the total effects into so-called Normal, Terrain, Topographical, Cartographical and Subterranean effects. This classification has been adhered to by most subsequent investigators, but the writer prefers to employ the term "three-dimensional," which really indicates the essential character of the class of effect known as "Subterranean," at any, rate from the standpoint of the computer of effects. Before disturbing effects can be eliminated, the features must be measured up or surveyed, whether by topographical, mining, or boring methods, and then the effects of each feature calculated and subtracted from the total observed effects. After this the problem of interpreting the residual effects will itself necessitate the computation of the assumed feature, or even a series of trial features.

Jan 1, 1928

By A. B. Kinzel

SINCE the exposition of the behavior of certain iron alloys by Sykes1 involving the existence of an austenite loop and the discovery of such a loop in the chrome iron system by Bain,2 there has been much conjecture both on his part and on the part of metallurgists in general as to the exact shape and location of this loop. In previous work commercial steel has been used and the microscope has been employed to locate the critical points so that the position of the loop has been quite approximate. Numerous attempts have been made to measure the critical points of the carbon-free alloys but all of these for one reason or another have failed. A satisfactory method for studying these phenomena, is presented here. MATERIAL The first difficulty in this study was to obtain pure chromium-iron alloys. This has been overcome by melting in a vacuum electrolytic iron and chromium analyzing 99.84 Cr, Fe and C. A pure magnesite crucible was used and the melt allowed to solidify in the crucible. A typical analysis is chromium, 10.10 per cent., carbon, 0.006 per cent., silicon and manganese nil. To overcome the problem presented by segregation, ingots were made into wire 0.04 in. in diameter. This was accomplished by hand-forging the ingots into rods, using an oxyhydrogen flame for heating, in order to avoid carbon. Subsequently the rods were swaged too wire, the heating being carried out in hydrogen. Thus local segregation was eliminated although differences in analysis between portions 50 ft. apart were noted. An electric-resistance method was first tried to determine the critical points, but due to the physical defects in the wire this failed. Bain had previously shown the presence or absence of critical points in a qualitative way by observing the sag in a catenary. The author has devised the following method which gives an accurate determination of the critical points from expansion-temperature curves of suspended wire, a special telescopic dilatometer being used for the purpose.

Jan 1, 1928

By H. M. Chance

WITHIN the last 10 years the subject of mine taxation in its relation to coal-mining interests has come to have growing importance, not only to those engaged in the mining of coal, but also to the owners of land underlain by coal. A disposition has developed among legislators to accept the principle, which has been laid down y many judicial decisions, that coal underlying the surface must be regarded as a part of the real value of all properties so underlain, and as such is chargeable with such burdens of taxation as the necessities of the government may impose. These necessities arise from the normal expense of maintaining State and local governments, and in the past have been met principally by, taxes based upon assessments of real estate values, which values in many cases have been confined principally or wholly to the value of the surface, without taking into consideration the value of minerals underlying the surface. It is not proposed here to deal with the question of Federal taxation, whether levied on production, or on products transported from one State to another, or exported from the country, or upon thegross or net earnings of corporations engaged in interstate commerce, or upon the production of materials which may be transported from one State to another, or levied. upon the profits or upon the obligations of corporations. The present discussion will be confined to the appraisal of coal lands as assessed for State, county, township, or borough taxation. The methods heretofore and at present in use in the different States vary widely and have resulted in more or less litigation. Discussions appearing from time to time in the technical and trade journals and in the proceedings of mining and engineering associations frequently direct attention to the need for the adoption of fixed principle in levying taxes, and of uniform methods for applying such principles, but there does not seem to be a general demand from the public for the adoption of such methods.

Jan 7, 1914