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By Walshe J. M.

The slow-speed compressor is giving place to the high-speed type, with its greater economy of material and space; and, where very large units are required, the turbo-compressor is supplying the need. In the very large air-supply stations on the Rand, turbocompressor units of a capacity of 20,000 and even 50,000 cubic feet, requiring 4,000 to 13,000 horsepower, are quite a commercial proposition, and have proved a practical success. Air-compressors of this size are, however, very exceptional, and the high-speed reciprocating compressor is quite capable of dealing with the highest outputs so far required in this country and, in the hands of manufacturers experienced in the design of high-speed steam-engines, a very high standard of reliability and efficiency in operation is obtained. The so-called “high-speed” or more correctly quick-revolution type of compressor is now extensively used in mines and collieries; for the air-pressures required for power purposes in mining work, two-stage compression, with an intercooler between stages, is the design usually adopted in best practice. It is not the writer’s intention to describe a variety of high-speed air-compressors but to select as an example of this type of compressor the one with which he is most familiar, and which is probably more largely used than any other, namely, the double-acting two-cylinder two-crank type with automatic light-plate air-valves, and with the working parts lubricated on the forced-lubrication principle. Sectional drawings, efficiency curves, air-cylinder diagrams and other data accompany the descriptions and photographs of compressor design, components and mine applications

Dec 1, 1916

By S a m u e l D e a n

The author's written response to previous discussion was presented at the North of England Institute of Mining and Mechanical Engineers general meeting held in Newcastle-upon-Tyne, 8 April 1916, followed by further comments by Hare S. in support of his view that the conditions in English mines were the reason for less satisfactory results being obtained with heading machines and brief comments by Greener T.Y., President

Dec 1, 1916

Discussion at the North of England Institute of Mining and Mechanical Engineers' general meeting held in Newcastle-upon-Tyne, 8th April 1916, on the paper published in Trans. I.Min.E., vol.LI, 1916, p.72-90, included written contributions on size and gauge standardisation by Lupton A., Peck W.R., Dean S., Mayer R.W. and Ashworth J., with the author's written response, and by Bulman H.F. and Brown M.

Dec 1, 1916

By Gibson J.

Further discussion at the North of England Institute of Mining and Mechanical Engineers' general meeting held in Newcastle-upon-Tyne, 3rd June 1916, on the paper published in Trans. I.Min.E., vol.LI, 1916, p.72-84, included a written contribution by Parfitt I.C. and the author's written replies to this and previous discussion

Dec 1, 1916

By Dean S.

Further discussion at the North of England Institute of Mining and Mechanical Engineers' general meeting held in Newcastle-upon-Tyne, 12th February 1916, with Mr. T.Y. Greener, President, in the chair, of the paper published in Trans. I.Min.E. vol.L, 1915, p.179 and 388. Written contributions to discussion included Mr. Dean's reply to earlier discussion (p.35-44), further written contributions by Tate S. (p.44-54) and Brown E.O.F. (p.54-56), and oral comments by Hare S., Merivale J.H., Greener T.Y. and Tate S. Particularly debated were the causes of the difference in output between American and British coal miners

Dec 1, 1916

By Hugh Rose

THE properties of the company lie within the Pachuca district, State of Hidalgo, Mexico, connected by three railway lines with Mexico City, 55 miles southwest, and by two lines with Vera Cruz, 250 miles southeast. The ores were formerly divided by sorting into two classes, smelting and milling, the former averaging about 2 oz. gold and 335 oz. silver, the latter 0.12 oz. gold and 23 oz. silver. The smelting ores were sold to custom plants, principally the American Smelting & Refining. Co. at Aguascalientes. The milling ores were treated by the patio process at the Guadalupe Hacienda, at Pachuca. This patio was probably the largest in existence at the time and continued in active operation up to March, 1910. In January, 1910, the mines and patio were sold to English interests, represented by Camp Bird Limited. Two new companies were formed, the Compañia de Santa Gertrudis, S. A., to operate the mines, and the Compañia Beneficiadora de Pachuca, S. A., to build and operate a custom cyanide milling plant. (Fig. 1.) GEOLOGY The historical geology of the Pachuca district is described by Fred J. Pope as follows: 1. The most recent sedimentary rocks in the district belong to the Cretaceous period. 2. The Cretaceous rocks were penetrated by large intrusions of ande-site (referred to hereafter as primary andesite) which occur as elliptical dome-shaped masses, striking northwest-southeast. These andesite bodies are from 8 to 15 miles long and from 6 to 10 miles wide. 3. A period of erosion during which the contour of the andesite domes was changed. 4. Andesite flows (secondary andesite) which rest unconformably on the primary andesites.

Jan 8, 1916

The Jeffrey Company Opens Branch in Seattle The Jeffrey Manufacturing Co. of Columbus, Ohio, announces the re-opening of its Northwestern Branch Office at Seattle, Wash., and the appointment of Mr. Percy E. Wright, Consulting Mechanical Engineer, as District Manager for Oregon, Washington, Alaska, British Columbia and Alberta. Mr. Wright, who has been in the Northwest since 1910, and whose connection with the Jeffrey company dates back to 1902, has' had a wide and varied experience and training in the handling of the Jeffrey line which will enable him to be of great assistance to customers in solving their elevating, conveying and transmission problems. Trade Catalogs To a majority of the public, the name 'DuPont suggests military powder-munitions of war. The DuPont Products Book A-430 (April, 1916) lists 251 distinct commodities made. and sold by this company, many of which are far removed from destructive work. Mining men are fully cognizant of the need for explosives in constructive work, but they may be surprised to know that side by side with the powder and dynamite this company manufactures such peaceful articles as substitute leather, combs and collar buttons. The substitute for leather is Fabrikoid, varying in weight from a quality light enough for bookbinding to one heavy enough for trunks and automobiles, and the combs and collar buttons (with scores of other articles) are made from Pyralin. The book also contains a long list of chemicals, and a shorter list of special products and miscellaneous materials such as charcoal, wood flour and saltpeter. The Jeffrey Manufacturing Co. of Columbus, Ohio, making elevating, conveying, crushing, screening and power transmission machinery, has just issued its. latest Bulletin, No. 177, :featuring self-propelling wagon and truck loaders for handling crushed stone, sand, gravel, clinker, coke, etc. These machines are described as having a capacity of 1 to 1 ½ cu. yd. of material per minute, with power to load crushed stone maximum size pieces through 3 ½ -in. ring and to load trucks or wagons in 3 or 4 min. The self-propelling device is designed to enable one man to operate the loader as it is fed into the pile, and to move the machine about under its own power.

Jan 7, 1916

By Grafton M. Thrasher

Discussion of the paper of GRAFTON M. THRASHER, presented at the New York meeting, February, 1916, and printed in Bulletin No. 106, October, 1915, pp. 2129 to 2138. RICHARD MOLDENKE, Watchung, N. J.-Mr. Thrasher is to be commended for developing a very interesting comparison between high- and low-carbon and silicon malleable cast irons for an equal degree of chill. His deductions are unquestionably correct, though the application to daily practice is open to serious criticism, from the standpoint of the man who receives the castings, as will be shown later on. Running over some of the points which affect the tests in question: Mr. Thrasher admits that the temperature of pouring has a serious influence on the degree of chill shown in the test plugs he made. This is a well-known fact, and I would like to add that another serious trouble comes from oxidized iron when the heats have been unduly prolonged. Such metal always shows more chilling action for a given silicon and carbon content than normally melted iron. Indeed, the test piece quoted giving the extreme of the chill line (1.07 per cent. Si and 2.47 per cent. total carbon) was such a poor heat, a ferro-silicon addition never "doctoring" up the metal sufficiently to show normal good strength. In spite of these irregularities, which would simply change the curve slightly, I take it that Mr. Thrasher's results can be accepted as reliable enough to establish the relationship of silicon and total carbon as shown. When, however, the claim is made that silicon and carbon can be substituted for each other in mixture-making (a claim which may be perfectly correct metallurgically), a very important factor is forgotten, causing the purchaser of the castings much annoyance. This is the contraction (erroneously called shrinkage) of the castings. They will no longer be true to pattern. The lower the total carbon is allowed to drop, the greater the contraction, and increasing the silicon correspondingly will not correct this trouble. No wonder that recently, in revising the Standard Specifications for Malleable Castings it was necessary to increase the variation of castings from requirements considerably over what was formerly found sufficient. The habit of running up the proportion of silicon and escaping danger from grayness of the metal by copious steel additions was evidently too tempting to manufacturers, as their molding losses were thus kept down and a very soft malleable iron resulted. The customer, however, got serious variations in his work, which was not the case when the total carbon was kept between 3.25 and 2.75, and the silicon held as low as possible without undue cracking of the hard castings.

Jan 5, 1916

By K. Huessener

Discussion of the paper of K. HUESSENER, presented at the New York. meeting, February, .1916, and printed in Bulletin No. -110, February, 1916, pp. 443 to 474. KARL NIBECKER, Youngstown, O.-It has been contended that the method of measuring the operation of a blast-furnace boiler plant by means of the amount of steam generated per pound of coke used in the blast furnace is not of any value and even that it is quite misleading. It has been found, in the plant with which I am connected, that, in general, a blast furnace will operate during a month so close to average. conditions that the average monthly measure of the plant efficiency is indicated by the number of pounds of steam made per pound of coke put into the furnace, neglecting the amount of iron made and the amount of gas used for heating the stoves. For some time, it has been our custom to keep a record of this figure and use it as a general indicator of the operating practice. In comparing this figure from two different plants we have found some difficulty, due to differing conditions. It is conceivable but not altogether probable that a slight difference in burden, kind of ore or coke, would account for this difference. The method of using the gas, whether washed or unwashed, and the plant arrangement, may affect this number. For several plants on which we have worked up this number, we have found that most of the ordinary running irregularities are eliminated during a run of a month or more and that the number is, therefore, satisfactory. In connection with a plot of the number of pounds of steam generated per pound of coke, we are also plotting the production of the furnaces and the pounds of coke used per ton of production. With these three curves plotted on the same sheet, we believe that the operating man has sufficient information to judge of the efficiency of his plant' for any month.

Jan 5, 1916

By Samuel Wyer

THE art of natural-gas compressing is now over 25 years old, and has grown at practically the same rate as the increase in domestic natural-gas consumers. There are now over 200 natural-gas compressing stations in North America, aggregating more than 320,000 hp. of compressor capacity and representing a property value of more than $22,000,000, and compressing more than 85 per cent. of all the gas used. The age and magnitude of the art make it evident that the use of gas compressors is a recognized integral part and universal custom of the natural-gas business. The public also is not without its rights and vital interests in this problem. Approximately 1,700,000 domestic natural-gas consumers in North America are dependent upon gas compressors for their natural-gas service. That is, if the use of compressors were to be prohibited, the majority of these consumers would be unable to secure adequate natural-gas service. Each consumer represents between four and five persons, and it therefore follows that the comfort and well-being-as far as natural-gas service is concerned-of at least 8,000,000 persons would be affected if the use of natural-gas compressors should be prohibited. These 1,700,000 consumers have invested, in services, house piping, fixtures, and appliances, an average of about $90 each, or an aggregate of $153,000,000, which is much more than the companies' investment in gas compressors. Furthermore, in all cases where the rate paid by the consumers is fair to the gas company-considering the value of the service rendered by the gas company-the consumers are entitled to continued service and protection of the investment they have made on the faith that the gas service would be continued in the future.

Jan 2, 1916

By H. F. Easter

The lead department of the El Paso Smelting Works at El Paso, Tex., is operated strictly on a custom basis. The ores treated are drawn from the surrounding territory, comprising New Mexico, Arizona, western Texas, and northern Mexico. Ores received from the last-named section originally amounted to a very large tonnage, but. of recent years have dwindled into comparative insignificance so far as this plant is concerned. This has been due partly to the establishment of a lead-smelting plant at Chihuahua, which is much closer than El Paso to most of the important mines, and partly to the recent revolutionary troubles in Mexico. There are no mines of either lcad or copper in the immediate vicinity of El Paso. In general, it may be said that the lead-ore supply of recent years has been uncertain and precarious, with a general tendency toward an excess of silica and a shortage of iron. This latter requirement has been met in large part by the use in El Paso lead furnaces of considerable amounts of roasted leady copper matte from the Chihuahua smeltery and of converter slag from the El Paso converters. These two materials, coupled with complex lead-copper ores from Bisbee, Ariz., have introduced into the lead-smelting operations a most unusual amount of copper, which has had an important bearing upon the smelting practice of the plant. his matter will be discussed later. The ore, loaded in either box cars or gondolas, enters the storage yard on four tracks elevated about 8 ft. above the ground. As all unloading is done by hand, unloading platforms at the height of the car floor parallel the tracks on each side to afford a runway for wheelbarrows. At frequent intervals these lengthwise platforms are joined together by others running crosswise to facilitate the distribution of the ores evenly over the beds, which are located below and between the tracks. At present much of the bedding space formerly used for lead ores is given over to the copper department, but 20 bins of various sizes are retained for the use of the lead furnaces and the Huntington & Heberlein roasting plant. The largest of these holds about 1,000 tons, while the smallest holds not over

Jan 1, 1916

By Samuel S. Wyer

The art of natural-gas compressing is now over 25 years old, and has grown at practically the same rate as the increase in domestic natural-gas consumers. There are now over 200 natural-gas compressing stations in North America, aggregating more than 320,000 hp. of compressor capacity and representing a property value of more than $22,000,000, and compressing more than 85 per cent. of all the gas used. The age and magnitude of the art make it evident that the use of gas compressors is a recognized integral part and universal custom of the natural-gas business. The public also is not without its rights and vital interests in this problem. Approximately 1,700,000 domestic natural-gas consumers in North America are dependent upon gas compressors for their natural-gas service. That is, if the use of compressors were to be prohibited, the majority of these consumers would be unable to secure adequate natural-gas service. Each consumer represents between four and five persons, and it therefore follows that the comfort and well-being—as far as natural-gas service is concerned—of at least 8,000,000 persons would be affected if the use of natural-gas compressors should be prohibited. These 1,700,000 consumers have invested, in services, house piping, fixtures, and appliances, an average of about $90 each, or an aggregate of $153,000,000, which is much more than the companies' investment in gas compressors. Furthermore, in all cases where the rate paid by the consumers is fair to the gas company—considering the value of the service rendered by the gas company—the consumers are entitled to continued service and protection of the investment they have made on the faith that the gas service would be continued in the future. Since "Customs adopted and acquiesced in, if not in conflict with federal or State legislation, have the force of positive law,"l and ('Courts will take notice of whatever ought to be generally known withxn the limits of their jurisdiction,"2 there ought to be no question as to the un-

Jan 1, 1916

By Edward Keller

The work covered by this report was undertaken at the request of Dr. J. A. Holmes, late Director of the Bureau of Mines, to whom the writer had been recommended by C. W. Goodale and E. P. Mathewson, of Butte and Anaconda, Mont. The director's offer was accepted for the honor it conferred and for the useful results that might be promulgated by the work in the technical field covered. The investigation was facilitated by permission to visit various works and sometimes by contributions of important definite information on a given subject. It is therefore with pleasure that acknowledgment of courtesies is made to the following corporations and gentlemen: Anaconda Copper Mining Co., Raritan Copper Works, Baltimore Copper Smelting & Rolling Co., United States Refining Co., American Smelting &, Refining Co., B. B. Thayer, A. C. Clark, A. L. Walker, William H. Peirce, E. A. Cappelen Smith, H. H. Alexander, F. C. Newton, S. Rolle, R. W. Deacon, N. W. Pierce, O. C. Martin, C. N. Sappington, James K. Thomson, W. G. Derby, and the assistants of the writer, K. W. McComas and W. L. Raup. In this report considerable space has been devoted to general and theoretical principles on the ground that under modern conditions the best results in any field of activity can be attained only with the a. id of an adequate knowledge of the best theories underlying the practice. The diffusion of such knowledge in the field of sampling metallic metallurgical materials appears to have been quite insufficient, and it is felt that when the principles involved are once thoroughly comprehended their universal application will be appreciated, so that it will make no difference whether pig iron or gold bullion is offered for test. It may further be noted that a discussion of the theories underlying practical methods is placed under the caption "Practical Sampling," with the idea that no one can be a practical sampler unless he is capable of analyzing his methods. No attempt has been made to advocate any one method, but it is hoped that the analyses of all of the methods in use will show where each may be correctly and safely applied. The fact that it is possible to demonstrate the theoretical correctness of several methods indicates the invalidity of the claim that any single one of them is the standard.

Jan 1, 1916

By John A. Davis, David W. Brunton

During the past few years great progress has been made in the United States toward safer, more efficient, and more economical tunneling methods. This advance is partly due, no doubt, to the recent increase in the number of tunnels and adits driven for devel- oping and draining mines and transporting ore. The Bureau of Mines during 1911 and 1912 made a special examination of this phase of mining operations, in connection with an investigation of mining methods and means for preventing accidents. The details especially studied were the provisions for the safety of employees, the kinds of equipment, the methods of driving, and the costs of con- struction. The results and conclusions obtained from that investi- gation are discussed and summarized in this bulletin. Up-to-date information concerning tunneling methods is difficult to obtain. There are few books on the subject; and much of the material they contain, although interesting and of value historically, is now obsolete. The engineering periodicals, it is true, endeavor to keep abreast of the times, and several in nearly every issue present some article bearing upon tunnel work. But the very multiplicity of these articles prevents one from reading them all, and the foreman or superintendent in charge of a tunnel, or the mining engineer designing one, and especially the business man financing the project, has no time for a lengthy search after scattered articles in order to determine the present status of tunnel work. Then, too, knowledge of new methods travels slowly. Valuable inventions and improve- ments in tunneling as well as in all the other industries frequently remain in the notebook of the investigator, or as theses are buried in university libraries, or are published only in journals of small scien- tific societies. New tunneling methods and equipment that are prov- ing safe, efficient, and economical may be totally unknown outside the district in which they originate. This paper, based on a special examination both in the field and in engineering literature, is in- tended to supply data concerning modern and recent tunneling practice in the United States, and to make suggestions that, it is hoped, will result in a saving to the mining industry of energy, capital, and life.

Jan 1, 1916

By A. S. Watts

The Bureau of Mines has been conducting an investigation of the feldspar resources of the New England and North Appalachian States with a view to greater efficiency and economy in their utilization. Such an investigation was deemed necessary, not only because of the continued and increasing consumption of these minerals, but especially because of the demand for better technical control of the raw materials that are used by the white-ware industries of the United States. Most manufacturers of white pottery wares have only a limited knowledge of the origin, mode of occurrence, and methods of mining and preparation of the materials that they use. Heretofore, owing to a belief that the supply of raw material was unlimited, the manufacturer had concerned himself chiefly with the solution of the problems of manufacture. Within the past few years, however, it has been found that difficulties arise in manufacture which can be traced beyond the manufacturing process and are believed to be due to a need of better control of the materials used. Furthermore, as competition becomes more severe, more attention must be paid to selection of materials in order to minimize consumption and also to avoid unnecessary expense for transportation of material. Doubtless the lack of interest as regards these details has arisen from the fact that in the past a considerable proportion of the whiteware ingredients has been imported and the manufacturer has been forced to rely on the samples submitted and the general uniformity of the source of supply to insure against variation of the material. An extra precaution arising from this lack of definite knowledge still prevails in the common practice of never depending on one source of supply for anyone ingredient. Often the products of three or more producers are blended so that if anyone shall vary without warning the variation arising from its use will not be sufficient to ruin the ware.

Jan 1, 1916

By WILLIAM F. McMURRAY, James O. Lewis

The Bureau of Mines is investigating the technology of petroleum and its products, the investigation including well-drilling methods and the transportation, treatment, and utilization of petroleum and of natural gas, with especial reference to the prevention of waste and to increased efficiencyin the development of oil and gas resources in land belonging to or controlled by the Government. During. the winter of 1912-13 the enormous waste of the gas encountered while drilling for oil in the Cushing field, Oklahoma, called forth protests from various sources, and appeal was made to the President of the United States and to the Secretary of the Interior in behalf of the landowner and of the public in general. The facts were wanted regarding the amount of waste and the technical conditions that were responsible for practices causing it. An investigation was ordered and conducted under the direct supervision of the late J. A. Holmes, the first Director of the Bureau of Mines. R. S.Blatchley was sent to investigate the amount of waste going on in the Mid-Continent flelds.s In the latter part of March, 1913, J. A. Pollard and A. G. Heggem were sent to Oklahoma to study well-drilling methods with reference to the waste of gas from wells on Indian lands and to suggest means of preventing the waste of natural gas on such lands. Pollard and Heggem decided that the mud-laden fluid process, which had been used successfully for some years in Texas, Louisiana, and California was the method that would meet the situation most efficiently and economically. The method was accordingly demonstrated in Oklahoma. In 1914 Congress provided for the employment of six oil and gas inspectors to supervise oil and gas mining operations on lands of the Five Civilized Tribes in Oklahoma and to conduct investigations with a view to the prevention of waste. Positions under this appropriation have been held by William F. McMurray, James O. Lewis, Harry D. Aggers, Ralph R. "Weed,George W. McPherson, James C. Fowler, Louis W. Courtney, and Carl H. Beal, the technical work of these men being directed "byW. A. Williams, chief of the petroleum division, Bureau of Mines. After careful and impartial investigation of conditions in Oklahoma, these men also decided that the mud-laden fluid process was the one best adapted to prevent further wastes. In 1915 laws were passed by the State of Oklahoma that provide for the conservation of natural gas and oil, authority being given to the corporation commission to make rules and regulations and to employ agents to enforce them. After hearings and investigations, the corporation commission reached substantially the same conclusions as the Federal agents regarding the importance of the wastes and the best methods of conserving the gas. Technical Papers 66a and 68b were published by the Bureau of Mines in December, 1913, and January, 1914, respectively. Technical Paper 66 deals with the mud-laden fluid process in general and No. 68 with its application in Oklahoma. The interest aroused by these publications has been so widespread that within two years the first editions have been practically exhausted. Rather than reprint these publications, it has been considered advisable to replace them with the present report, which includes the results of more recent investigations. The methods of using the mud-laden fluid are an outgrowth of the rotary drilling system, which was developed in Texas and later employed in Louisiana and California. Some of the principles of the use of mud fluid had been observed and used to a limited extent for a long time in cable-tool drilling. So far as known it was first used successfully with a circulator and cable tools in the Coalinga field, California, in 1906,Harry D. Aggers, one of the contributors to this paper, working on the well. The part of the Bureau of Mines has been to call attention to its merits and to demonstrate its practical use in fields like those of the Mid-Continent.

Jan 1, 1916

By J. W. Thompson

A contract stipUlating for the delivery of quantities of phosphate rock" f. o. b. mines," and stipUlating that" while this contract is in form an absolute sale for a fixed quantity in each year, it is mutually understood and agreed that the purchase is for the buyer's consumption and not for a sale; the buyer agreeing to give to seller the refusal of any surplus over and above the actual consumption. Buyer is at liberty to increase or diminish the quantity called for in any year, to the extent of not exceeding 10 per cent; provided that the quantity to be taken shall not be less than buyer's consumption; provided further that notice of such increased or diminished demand be given seller 12 months in advance of such change," is to be construed as a contract for the sale of stated quantities of rock, deliverable in approximately equal quantities during each year for the specified series of years, subject only to be increased or diminished after specified notice in any year, where the amount taken would not be les<; than the buyer's consumption, not exceeding 10 per cent, and the contract indicating that the rock was intended by both parties for consumption in the fertilizer plant of the buyer. but the quantity to be taken was not limited by the necessities of' the plant.

Jan 1, 1916

By J. W. Thompson

OIL AND GAS AS MINERALS. Oil and gas within the ground are minerals and the fact that they have attributes not common to other minerals because of their fugitive nature or vagrant habit, and the disposition to percolate, and the possibility of their escape from beneath one part of the surface to another, does not remove them from the class of minerals. Texas Co. v. Daugherty (Texas), 176 Southwestern, 717, p. 719, May, 1915. OWNERSHIP OF TAILINGS-ABANDONMENT. A corporation engaged in milling- and the reduction of ores deposited the tailings therefrom upon a portion of its own land lying in a gulch through which water flows at times in great volumes and with great force' and notwithstanding all reasonable efforts by dams and otherwise to retain its tailings, the tailings eventually were forced upon the lands of an adjoining owner; these tailings were valuable and their retreatment, intended by the mill owner, profitable; and the fact that the tailings were so washed down upon the lands of the adjoining owner and permitted to accumulate and remain for some considerable time is not sufficient to show an abandonment on the part of the owner of the tailings, where it is clear that the owner had no intention of so doing, but on the contrary, always intended to conserve and retreat the tailings.

Jan 1, 1916

By J. W. Thompson

SALE AND CONVEYANCE. DEED BY INDIAN ALLOTTEE OF UNSOUND MIND-BONA FIDE PURCHASER. The deed of an Indian allottee whose mind was unsound, but who was not entirely without understanding, is voidable if made before the grantor's incapacity has been judicially determined; and a purchaser of the original grantee who interposes the defense of a bona fide purchaser has the burden of showing a purchase for value and on failure to do so can not claim the benefit of a bona fide purchaser. Adams Oil & Gas Co. v. Hudson (Oklahoma), 155 Pacific, 220, February. 1916. PURCHASER OF MINING CLAIM-RIGHT TO FIXTURES. The purchaser of a mine equipped with an electric hoist, placed in the mine under a rental contract with the owner of the hoist and under an agreement to return it to the owner at the expiration of the term of hiring, can not claim and hold the hoist as against the owner where the agent of the seller explained to the purchaser that the hoist was not owned by the owner of the claim. Montana Electric Co. v. Northern Valley Mining Co. (Montana), 153 Pacific, 1017. p, 1018, October, 1915. AUTHORITY OF GRANTEE TO EXTEND LEASE. A deed conveying lands subject to an oil and gas lease under which the lessee had the right to drill or pay money in lieu of drilling at his option, and reserving to the grantor a share of the royalties under such lease, and expressly authorizing the grantee to lease the land for oil and gas purposes and to take the rentals, authorizes the grantee to extend the existing lease before the expiration thereof in consideration of the annual payment of money in lieu of drilling, as contemplated by the lease.

Jan 1, 1916

By D. A. Lyon

Discussion of the paper of DORSEY A. LYON and ROBERT M. KEENEY, presented at the San Francisco meeting, September, 1915, and printed in Bulletin No. 104, August, 1915, pp. 1707 to 1730. LAWRENCE ADDICKS, Douglas, Ariz.-I think papers of this character, while general in, nature, are of particular value and interest, because when we figure on competing with the East in electrometallurgical industries, on account of the cheap power on the Pacific Coast, we have to take two or three things into account. In the first place, power very rarely amounts to more than 20 per cent. of the total cost of an operation, even .though it be electrometallurgical, and I think it is the common opinion among those who are not familiar with those particular industries, that it amounts to more than 50 or 60 per cent. Take copper refining; we may say that it is 15 per cent. of the total cost. In the second place, around New York City, with 100 per cent. load factor and a reasonably large load, say 10,000 kw., we can generate from a certain class of coal 1 kw.-hr. for about 0.3c. I might say, however, that 0.3c. does not include overhead charges, interest on the investment, etc. The third factor we have to consider out here is that any product to be salable, must command a retail market. It would be useless to produce wire bars here on the Pacific Coast because there is no place to roll them. If we were going to establish a copper refinery, that part of its output which goes into wire bars would have to be taken care of by building a rolling mill alongside of it to turn it into wire and finally make a product that is salable. I do not think, however, that Mr. Lyon need have excluded copper refining from his industries. There are perhaps 50,000,000 lb. of copper a month refined in this country on a custom basis. I think the smelting companies would be very glad to build refineries here if conditions warranted it. The recent extensions of the Great Falls refinery and of the Tacoma refinery in the last few months give evidence of that.

Jan 12, 1915