in charge of the work, assisted by other members of the metallurgical staff of the bureau assigned to duty at Salt Lake City. After organizing the work of the station at the University of Utah and supervising the research problems for nearly three years, Mr. Lyon was assigned to duty at the new station in the Northwest.

The staff at present assigned by the Bureau of Mines to the department consists of: The metallurgist in charge, a metallurgist, an assistant metallurgical engineer, a metallurgical assistant, a geologist and microscopist, a junior chemist, a chief clerk, a junior clerk, and a stenographer.

The University of Utah is providing the building and the greater part of the equipment, and also five metallurgical research fellowships of the yearly value of $720 each. The fellowships are awarded to graduates of colleges, preferably of mining schools, who have shown special aptitude for research investigations. Their employment extends over the entire twelve months.

The administrative head of the department is the director of the State school of mines. No employee of the United States Bureau of Mines has anything to do with the handling of the funds appropriated by the State for supporting the department. The laboratory work of the department is for the most part carried on in the metallurgical building. Due to this fact the department is in close touch with those in charge of the work in mining and metallurgy that is being carried on by the university for the benefit of undergraduate students doing work in these subjects. Moreover, it has received valuable assistance from those in charge of this work, and in this connection grateful acknowledgment is made of the help given by Dr. Robert H. Bradford, professor of metallurgy, and Robert S. Lewis, professor of mining, to those in charge of the work of the department of metallurgical research. Without their help, and the untiring efforts of the director of the State school of mines, the department would not have been able to accomplish the work it has done.

The fellows selected by the university authorities for the fiscal year 1913-14, and the problems assigned to them, were: L. F. Pattison, A. B., University of Utah (Hydrometallurgy of copper); W. G. Woolf, A. B., University of Utah (Hydrometallurgy of zinc); O. H. Pierce, A. B., University of Nebraska (Metallurgy of copper); A. E. Gartside, A. B., University of Oklahoma (Hydrometallurgy of zinc); and C. Y. Pfoutz, E. M., University of California (Hydrometallurgy of silver).

Messrs. Pattison, Gartside, and Pfoutz resigned their fellowships at the end of the fiscal year, and those selected, from a large number of applicants, to take their places for the fiscal year 1914-15, and the problems assigned to them, were: R. M. Isham, Ph. D., Columbia University (Smoke problems); C. L. Larson, E. M., University of Minnesota (Hydrometallurgy of lead); and H. J. Morgan, A. M., Stanford University (Flotation of oxidized ores).

Messrs. Isham and Pierce resigned shortly after entering the department and their places were taken by Messrs. Herbert J. Cutler, of the University of Michigan and Frank Cameron, of the University of Utah.

The fellows selected for the year 1915-16, and the problems assigned to them, were: Marvin J. Udy, University of Utah (Hydrometallurgy of lead); Richard W. Johnson, University of North Dakota (Hydrometallurgy of zinc); Clarence E. Sims, University of Illinois (Electrolytic precipitation of metals); Glenn L. Allen, University of Kansas (Flotation of oxidized lead ores); Harper C. Neeld, University of Nevada (Concentration of oxidized zinc ores); and George F. Stott, University of Utah (Milling losses in Utah).

The fellows appointed for the fiscal year 1916-17, and the problems on which they are working, are as follows: Edward J. Atckison, University of Oregon (Ore flotation problems); Theodore Erickson, University of Utah (Utah hydrocarbons); Charles W. Frith, University of Utah (concentration of oxidized zinc ores); Arthur J. McChrystal, resident of Eureka, Utah, Stanford University (treatment of complex sulphides); Grover J. Holt, University of North Dakota (hydrometallurgy of lead);

Orel E. Young, Case School of Applied Science (hydrometallurgy of zinc); Leonard D. Yundt, University of Utah (flotation oils); Clyde E. Williams, University of Utah (igneous concentration of lead).

Beside the work initiated and conducted directly by the department of metallurgical research, cooperative work has been carried on with institutions, and mining and metallurgical companies, who have had problems similar to those upon which the department was working. In these cases, men have been sent to work in the laboratories of the department by the cooperating concerns, these men carrying on their investigations under the same rules as are applied to the "fellows" of the department. The discoveries which they make are the property of the department to be given to the people of the State through publications and otherwise.

As cooperators the department has the following: Utah State Conservation Commission. (This institution subscribes to the salary of an analyst in the departmental laboratory for examination of material brought in by prospectors of the State): McKeever Brothers, of New York; Prince Consolidated Mining Co., of Pioche, Nevada; Big Indian Copper Co., of Utah; Grand Central Mining Co., of Utah; Zinc Concentrating Co., of Boston; Utah Minerals Concentrating Co., of Eureka, Utah; United States Forest Products Laboratory, Madison, Wisconsin; and The General Engineering Co., of Salt Lake City.

Also, the following individuals have cooperated: E. H. Synder, of Pioche, Nevada; E. T. Cannon, of Salt Lake City; Dr. W. L. Ellerbeck, of Nephi, Utah; Prof. H. K. Benson, University of Washington; and C. T. Van Winkle, of Salt Lake City.

At the present time the annual appropriation made by the United States Bureau of Mines for the work in connection with this station amounts to about $15,000, and the authorized appropriation of the State of Utah is $7,500. Also, outside cooperating agencies are spending considerable money for the specific work carried on by them in this department. At the time of writing this report, five men, employed by cooperating concerns, are at work in the laboratories.

The Bureau of Mines has established at the University of Utah probably the best equipped microscopic laboratory in the West for metallurgical research work. This microscopic and metallographic examination work is being conducted by Dr. F. B. Laney, who was detailed to the bureau by the United States Geological Survey.

Below are shown the amounts that have been expended by the United States Bureau of Mines and the State of Utah in conducting the cooperative work which is being carried on by the department of metallurgical research.

Three main problems in the treatment of lead ores had troubled metallurgists for many years and were still largely unsolved at the time the Salt Lake City station was established. These problems were as follows:

1. The treatment of lead carbonate ores with or without gold and silver.

2. The treatment of complex sulphides of lead and zinc either with or without metals other than lead or zinc.

3. The recovery of sulphide of lead from the finely divided "slimes" of the concentrating mills.

The third problem, that of prevention of losses in slimes, was being solved in a number of mills at the time the station was established. Flotation methods were just beginning to attract the interest of the general public. After some investigation it was decided that the most useful work of this sort that the station could perform would be the gathering and dissemination of information relating to the flotation process, rather than testing samples of the slimes submitted, because the flotation industry seemed to be in a healthy condition and the mill operators were willing to do their own testing in the attempts to prevent losses. Nearly every lead concentrating mill of any size that formerly suffered serious losses of galena in slimes has now a flotation unit to increase the recovery of metal.

OXIDIZED ORES OF LEAD.

In nearly every mining district where lead is found to any extent, the lead in the upper or weathered parts of the ore deposits, generally above the level of the ground water, is oxidized, being usually in the form of the carbonate, and occasionally the sulphate of lead. In most of the Western States the lead carbonate is, as a rule, accompanied by silver and occasionally by some gold or copper. Much of this "carbonate" ore has been very rich, owing to natural concentration by weathering. Such ores because of their richness and their needing for the most part no roasting before smelting have contributed greatly to the development of the mines.

Wherever the "carbonate" ore has been low-grade, however, preliminary concentration has been necessary. In milling such ore, serious losses in the tailings often have taken place, owing to the well-known tendency of lead carbonate to "slime" by breaking into thin flakes that float away with the gangue. The concentrates obtained by gravity concentration have usually been of good grade and in demand by the smelters. Dumps of these slime tailings abound in almost every important base-metal mining district of the western United States, and in regions where oxidation extends to any depth there are vast quantities of such low-grade ores from which the high-grade ore has been gouged out. In fact, in many districts the custom has been to mine only the ore of smelting grade and to leave the lower grade material in the mine. That ample supplies of low-grade oxidized ores of lead are available and that much of this material is being wasted can not be doubted.

MATERIALS TESTED.

The results of analyses of representative samples of ores, tailings, and slimes containing oxidized lead are shown in Table 1. All of these materials are not completely oxidized, as some of them contain noteworthy amounts of lead sulphide. The sample from the tailings dump of the Horn Silver mine contained a larger proportion of the lead as the sulphate, anglesite; also the rather high zinc content consisted of the sulphide, sphalerite. Hence a further classification of these materials may be made, as has been done on page 168, when the individual peculiarities of each are considered with regard to its adaptability to various methods of treatment.

Mineralogical analysis of such oxidized materials is difficult, as they are often so "ocherous" that individual minerals can not be distinguished, whereas the minerals usually have few characteristics by which they can be distinguished optically from each other. It was found that an idea of the mineralogical association of the lead could be obtained by treating the material with certain solutions. A saturated solution of brine or a neutral solution of ammonium acetate, if used in excess, will dissolve all of the lead sulphate in the material; hence, this method was used for determining that constituent. After such treatment acidified saturated brine (salt solution) or acid ammonium acetate solution will quickly dissolve all of the lead carbonate. If the material being treated is left too long in contact with the solution, some of the sulphide of lead will also be dissolved, and a short time of contact with the warmed solution was found advisable. As acidified brine was used in one of the proposed methods of treatment, this figure was of practical value. Few minerals of lead other than the sulphate and the carbonate occur in such material in commercial amounts; hence, no other tests were necessary. The molybdate of lead, wulfenite, and the chlorophosphate, pyromorphite, can occasionally be found in small amounts. In material from the Nevada United mine the dioxide of lead, plattnerite, was also identified.

The results of mineralogica analyses of some of the materials tested with respect to the lead by the method discribed in the preceding paragraph are shown in Table 2.