Search Documents

Jan 1, 1892

Paper withdrawn from publication September 8,1977, after book was printed. Pages 258.272 are therefore omitted.

Jan 1, 1977

By Persifor Frazer

(Read at the Wilkes-Barre Meeting, May, 1877.) A CLASSIFICATION of natural objects is usually based either upon some fundamental and permanent attribute of the thing itself (as in the case of scientific classifications), or it embraces one or more generalizations convenient for use in ordinary life. Thus, it suffices for the statistician to, know that so many tons of fish are annually taken by our fishermen, and that they realize so many thousands of dollars, whereas to the student of natural history the anatomy, habits, and relationships of the animals are of chief interest, as settling their respective places in the scale of animate nature. Many different classifications of coals have been attempted, as one would naturally anticipate from the immense extent of the coal trade, and the different localities whence the supply was derived. The English divisions were prevalent up to the date of the publication of the last geological survey of the State, except so far as they were modified by local designations. Indeed, Rogers' classifications made very little alteration in the English nomenclature, as may be seen by comparing. the tables given below. To commence with the different kinds mentioned in Ure's Dictionary of Arts, Manufactures and Mines of 1845 " 1. Cubical Coal.-Black, shining, compact, moderately hard and easily frangible. Comes out in rectangular masses, of which the

Jan 1, 1878

GEORGE OTIS SMITH, the Institute's new presi-dent, continues the long tradition of close asso-ciation between the organization and economic geology. Several preceding presidents have been eco-nomic geologists, and a gen-erous share of space in the TRANSACTIONS has always been devoted to that subject, one of critical importance to the miner as well as the seeker for ore. Mr. Smith has long served the Institute, hav-ing been a director since 1921 and first vice-president since 1927. He was born in Hodg-don, Me., on Feb. 22, 1871, and graduated at Colby College, where he took his A.B. and A.M. He did graduate work at Johns Hopkins, where he re-ceived a Ph.D. in 1896. Meanwhile he had engaged in field geological work in Michi-gan, Utah and Washington with the Geological Survey. In 1896 he joined the regular staff of that organization, be-coming director in 1907. He has been with the Survey con-tinuously since he first joined, with the exception of one year when he was furloughed to serve as a member of the U. S. Coal Commission. His special interest for many years has been in the eco-nomic aspects, in the larger sense, of the mineral in-dustry, matters that are necessarily the subject of strong differences of opinion, but which he has dis-cussed with good temper though with full adherence to his strong con-victions.

Jan 3, 1928

Application of Kutter's Formula to Gases Discussion of paper by F. ERNEST BRACKETT, presented at the Pittsburgh Meeting and issued, as Pamphlet No. 1578-A-F, with MINING AND METALLURGY, June. 1926. C. S. WITHERELL, New York, N. Y. (written discussion).-There is no reason to doubt that the relationship between the rate of flow and the impelling force of all fluids can be expressed by a general typical equation . that takes cognizance of all relevant factors such as density, viscosity (or its reciprocal mobility) and nature of channel-walls. Most fluids that are commonly conveyed by flow in confined channels are so highly mobile that they may be considered non-viscous, hence for these fluids the factor of viscosity does not need to appear in the equation. Water is the outstanding example of this class of fluids and its dynamic behavior has been so thoroughly investigated that proven formulas pertaining thereto, be they rational or empirical, would naturally serve as prototypes for the other non-viscous fluids. As non-viscous fluids can be classed all gases and vapors, most unsaturated aqueous solutions, gasoline, alcohol, etc. Viscous fluids comprise those that have a sluggish flow such as most. oils, tar, molasses, etc., the high viscosity of which is due to shearing resistance between molecules; a force that must be taken into account in figuring the flow of fluids of this class.

Jan 10, 1926

Application of Kutter's Formula to Gases Discussion of paper by F.-ERNEST BRACKETT, presented at the Pittsburgh Meeting and issued, as Pamphlet No. 1578-A-F, with MINING AND METALLURGY, June. 1926. C. S. WITHERELL, New York, N. Y..(written discussion).-There is no reason to doubt that the relationship between the rate of, flow and. the impelling force of all fluids can be expressed by a general typical equation that takes cognizance of all relevant factors such as density, viscosity (or its reciprocal, mobility) and nature of channel-walls. Most fluids that are commonly conveyed by flow in confined channels are so highly mobile that they may be considered non-viscous, hence for these fluids the factor of viscosity does not need to appear in the equation. Water is the outstanding example of this class of fluids and its dynamic behavior has been so thoroughly investigated that proven formulas pertaining thereto, be they rational or empirical, would naturally serve as prototypes for the other non-viscous fluids. As non-viscous fluids can be classed all gases and vapors, most unsaturated aqueous solutions, gasoline, alcohol, etc. Viscous fluids comprise those that have a sluggish flow such as most oils, tar, molasses, etc., the' high viscosity of which is due to shearing resistance between molecules, a force that must betaken into account in figuring the flow of fluids of this class.

Jan 10, 1926

Weiss Transit and Level The illustrations shown are the transits and levels manufactured by the Weiss Instrument Co. of Denver, Colo:, and they state that city and mining engineers are securing satisfactory results. It is claimed that their patented prismatic telescope gives increased illumination with an astronomical eye-piece. The prisms are set in a milled seat for this purpose, and cemented in so they can never come loose or out of adjustment. All adjustment for collimation is clone with the cross-hairs. This telescope is 8 in. long for magnifying power of 20 diameters against 12 in. for regular old style. The field is 1° 45' with a clear aperture of 1 1/8 in. The standards are 4 ¾ in. high from plate; to center of telescope axis. Weight 10 lb. Fig: 2. FIG. 1. FIG;. 3. The Light Mountain Transit of the same type, Fig. 1, has a telescope 6 ½ in. long, magnifying power 17 diameters; field 2° 15'; clear aperture 1 1/16 in.; weight 9 lb. The Mine Transit made by this ?company is interesting because it may be sighted directly down a shaft.. The principal advantage claimed for this type is the arrangement by means. of which vertical' sights can be had without an additional telescope.. As illustrated in Fig. 2 the telescope is in the position of a regular transit, and used exactly the same.

Jan 10, 1915

Jan 1, 1953

The American Mining Congress, 841 Munsey bldg., Washington, D. C. J. F. Callbreath, Secretary. The American Mining Congress is a trade association rather than a technical society and as such does not issue scientific papers. Aside from the articles appearing in the monthly Mining Congress Journal, and the Proceedings of the Annual Meetings, only two works have been issued. They are: The standard handbook on mining methods, practice and equipment. $3.

Jan 1, 1933

Jan 1, 1957

By E. L. Raymond

The effect of heat treatment on the microstructure and resultant notch-bar rupture life of ZNCONEL alloys X- 750 and 718 was studied. It was found that the primary effect of heat treatment in rendering these alloys notch-ductile is the elimination of any y' denuded zone adjacent to the pain boundaries. The mechanisms by which such a denuded zone can arise and be eliminated by heat treatment are discussed. InCONEL Ni-Cr alloy X-750 and INCONEL Ni-Cr alloy 718 are age-hardenable austenitic materials. Alloy X-750 is used for its corrosion and oxidation resistance and high creep-rupture strength up to 1500°F. Alloy 718 is used most effectively up to 1300°F. One of the most important areas in their development has been establishment of consistently good rupture properties, especially in the presence of a stress concentration, such as imposed by a notch. A desire to improve these properties has led to extensive studies of the effect of heat treatment on the micro structure of these alloys and their performance in stress-rupture tests. In earlier investigations"~ of INCONEL* alloy X-750, *INCONEL i s a Registered Trademark of The International Nickel Co., Inc. grain boundary carbide morphology was linked with stress-rupture properties. If, during heat treatment, the carbide MZSC was precipitated in the grain bound-ary in a cellular form, poor rupture properties re-

Jan 1, 1968

[Trans. No. Place Date Vol. Page 1. Wilkes-Barre, Pa.* May, '71.. 1 3 2. Bethlehem. Pa Aug., '71.. 1 10 8. Troy, N. Y Nov., '71.. 1 1S 4. Philadelphia, PaFeb., '72.. 117 5. New York, N. Y.*May: '78.. 120 5. Pittsburgh, PaOct., '72.. 125 7. Boston, MassFeb., '78.. 128 8. Philadelphia, Pa.* May, '78.. 2 3 9. Easton, POct., '78.. 27 10. New York. N. YFeb.. '74.. 2 11]

Jan 1, 1946

By Charles W. Dickson

CONTENTS. [ ] I.THE RELATION OF NICKEL TO PYRRHOTITE. Introduction. The Sudbury district is to-day one of the two great sources of nickel in the world. The peculiar geological relations of

Jan 1, 1913

By T. V. Falkie, Robert Stefanko

Much criticism has been directed at the Coal Mine Health and Safety Act of 1969 from many sources, but few specific charges have been leveled, at least publicly. Yet, if the criticism is truly valid and can ever hope to become constructive, the issues must be approached head on. Therefore, the authors consider this an initial article and invite responses from others for contributions in subsequent issues. Dialogue is today's popular term and perhaps many of the problems associated with the implementation of the Act are the lack of communication between interested parties. There are two criticisms generally made concerning the philosophical approaches taken in the Act. The first is that there is an over-kill in some of the legislation, some provisions are not justified based on past accident history and economic considerations. Generally speaking in this category, no order of priority was considered consistent with safety and economy. The second category includes those situations where new provisions were imposed to improve safety in one area without adequately considering the consequences in another area, let alone the economics of the situation. While the authors do not always agree with the placement of items in these two categories by some industrial representatives, they will give specific examples that they believe may have a certain degree of validity.

Jan 1, 1971

Meeting of Oct. 23, 1914.-It was voted to take no action concerning the proposed amendments to Article VIII, Sections 2 and 3, but that they be sent to the membership, as provided by the Constitution, together with a statement of the arguments for and against the proposed changes. It was voted that the following proposed amendment, which had been unanimously approved at the annual meeting of the Institute on Feb. 18, 1914, be sent to the membership as provided by the Constitution, together with the approval of the Board of Directors of this change: Article III, Section 1, paragraph 3, sentences 2 and 3: substitute the following: "Any Member, Junior Member or Associate in arrears for two years shall be dropped from the rolls unless the time for payment is extended by the Directors. A Member so dropped may be reinstated by the Directors on paying the arrears of clues and other indebtedness with which he was charged on the books of the Institute it the time he was dropped. A Member or Associate thus reinstated shall receive the Transactions for the back year for which he pays." It was unanimously voted to extend the sincere thanks of the institute to Samuel A. Taylor, Chairman, and to each member of the several Committees of the Pittsburgh meeting, for the enjoyable and successful meeting which they brought about.

Jan 12, 1914

By J. F. Tavernelli, L. F. Coffin

The deformation and fracture characteristics of eight metals subjected to fully reversed cyclic strain ranging from 0.2 to 50 pct were investigated at room temperature. Strain-hardening characteristics unique to the interna1 structure of a particular metal were found. Complete removal of the strain-hardening effects resulting from prior deformation was brought about by subsequent cyclic strain. Further support for the validity of the inverse relationship between the plastic strain range and the square root of the number of cycles for failure is given. THE resistance of materials to cyclic plastic strain is of interest both from a fundamental and practical point of view. It is now a well-accepted fact that fatigue failure in metals is a consequence of the localized slip deformation which occurs within the individual crystals of metal.'-' Hence the failure process should be strongly dependent upon the magnitude of the gross cyclic plastic deformation of the metal under conditions where this is a measurable quantity. Therefore, an experimental investigation of metals in which the cyclic plastic strain is the independent variable should shed new light on some of the basic aspects of the problem. From the practical point of view, there are many uses for information relating to the cyclic strain resistance of metals. One is the case of thermal stress fatigue where fatigue failure can occur as a consequence of a com- paratively few cycles of thermally induced mechanical deformation. Another is the mechanical working of metals where large cyclic strains are employed. In recent years several publications have appeared relating to the cyclic-strain resistance of metals,8-11 dealing mostly with the fracture aspects where the temperature is cycled simultaneously with the mechanical strain. Some work has been reported on the cyclic-strain resistance of metals at constant temperature, again oriented more toward the fracture aspects of the problem than the deformation aspects. 12-16 The present research investigation was undertaken to obtain information regarding the deformation characteristics of several metals whose structure-property relationships were simple and straightforward under conditions of both cyclic and monotonic strain. It has been shown for example that under cyclic-strain conditions some materials will strain harden, while other materials, particularly cold-worked structures, strain soften and these effects required further clarification.8,17-19 It was also de-

Jan 1, 1960

Jan 1, 1942

New Products Equipment

Jan 8, 1951

Jan 1, 1930

By W. F. Boericke

THE character of the Wisconsin orebodies must be clearly understood to appreciate the difficulties encountered in sampling and estimating them. Unlike the western vein deposits, they do not lie between regular walls, but form large, often highly irregular bodies, on a single floor in the so-called Galena limestone. The bottom of the ore is nearly always on the clay bed, a flat generally well-defined clay seam a few inches thick, which marks the junction of the base of the Galena lime and the top of the next formation, the Trenton lime. Above the clay bed, the orebodies make the unique pitch and flat formation described by Chamberlin.1 Theoretically, we should find two pitches, one on either side of the top crevice, diverging as they go down, with the final flats a considerable distance apart on the clay bed. The area between, known locally as core ground, should thus constitute a single defined orebody, with the richer portions near the pitches and the leaner portion in the center of the core. Practically, we find few examples of this perfect orebody. Almost invariably one pitch is better defined than the other, and often the opposite pitch is marked only by a faint line of fracture showing stronger mineralization than the wall rock, or it may be totally lacking. But with an orebody of any size or richness, at least one strong pitch usually tends to follow an east-west trend, or a quartering course. Late mining developments in the rich New Diggings field indicate that these pitches often assume a horseshoe or crescent shape, the richer ore being in the heart of the crescent and the pitches showing less mineralization as they extend outwards. In the northern end of the field, on the contrary, the pitches maintain generally a consistent direction, and have been mined for thousands of feet from the shaft. The length of the orebody may be several thousand feet, the height varying from 10 to 60 ft. and the width from 60 to 250 ft. In fact, on the core side, there is no definite end to the ore. The mineralization simply gets thinner and thinner, and the limit of working depends on the cost sheet and the profit from the recovery.

Jan 2, 1922