tom assays for a nominal charge, there being no commercial assayer at present in the district. Seventy-four assays were made during

Both the superintendent and the metallurgist of the station visited mining districts in order to become acquainted with operators, their problems and needs, and to give advice and assistance. On one of these trips Mr. Davis went to Cape Prince of Wales, visiting the mining districts en route.

A large proportion of the sixteen hundred visitors at the station. during the year called to take advantage of the technical library, reading room, and mineral collection.

SUMMARY OF INVESTIGATIONS.

The following table summarizes the more important investigations of the station during the year:

John A. Davis was superintendent of the station, John Gross, metallurgist, and Paul Hopkins, chemist.

GOLDEN STATION.

HELIUM INVESTIGATIONS.

During the year R. B. Moore, superintendent of the Golden station, was in charge of the three experimental helium plants in Texas for producing helium, and was away from the station much of the time. An account of the work done by the Bureau of Mines in Texas appears on pages 678 and 679.

INVESTIGATIONS OF RADIUM.

CHEMICAL EFFECT OF RADIUM EMANATION.

During the year S. C. Lind, physical chemist, made an exhaustive study of some of the chemical effects of radium emanation in gas reactions. The combination of hydrogen and oxygen to form water was studied in glass spheres differing in diameter by 1 to 5 centimeters. The chemical effect of "recoil atoms" was demonstrated for the first time and shown to be proportional to the ionizing effects, as in the case of alpha particles. These researches are described elsewhere."

a Lind, S. C., Chemical action produced by radium emanation: Jour. Am. Chem. Soc., vol. 41, April, 1919, pp. 351-551; pp. 551-559.

DETERMINATION OF SILICA IN RADIUM-BARIUM SULPHATES.

C. W. Davis, junior chemist, worked out methods for determining silica in, radium-barium sulphates, the ordinary radium concentrates in the manufacture of radium.

NEW DEPOSIT OF URANIUM ORE.

A new deposit of uranium ore near Lusk, Wyo., supposed to be uranophane, a hydrated silicate of uranium and calcium, was examined by Dr. Lind; analytical determinations were made by C. W. Davis. This is the first uranium ore, besides carnotite and pitchblende, to be found in commercial quantity in the United States. A preliminary description of the deposit and the ore was published in Science."

SPECTRUM OF THE RADIUM EMANATION.

In cooperation with the bureau, Prof. R. E. Nyswander, of Denver University, is redetermining the spectrum of the radium emanation. This work is incomplete.

ZIRCONIUM.

Dr. J. W. Marden, associate chemist, M. N. Rich, assistant metallurgist, and L. W. Dunham, junior analytical chemist, worked on zirconium with the object of determining first, the properties of the pure metal and, second, new methods for making the pure oxide for commercial purposes. A satisfactory method for obtaining pure zirconium oxide has been developed, and a considerable number of samples of the pure metal have been prepared and their properties determined. The results will be published by the Bureau of Mines.

WORK ON MOLYBDENUM.

FLOTATION OF MOLYBDENITE ORES.

Under a cooperative agreement between the Primos Exploration Co., with mill and mines at Empire, Colo., and the Bureau of Mines, the best methods of flotation for recovering molybdenite from ores were studied. W. H. Coghill, of the Seattle station, and J. P. Bonardi, of the Golden station, worked in the station laboratory and in the mill of the Primos Exploration Co. An increased recovery of between 15 and 20 per cent was obtained, which meant a saving of over $1,000 a day to the company when the mill was running at full

Lind, S. C., and Davis, C. W., A new deposit of uranium ore: Science, vol. 49, May 9, 1919, pp. 441-443.

capacity. The results of this work will be published by the bureau under the title "Experimental and Commercial Flotation of Molybdenite."

MICROSCOPIC EXAMINATION OF ORES.

In connection with the above work, Mr. Coghill and Mr. Bonardi developed methods for the microscopic examination of ores, which were described in a technical paper, "Approximate Quantitative Microscopy of Pulverized Ores," now in press.

DETERMINATION OF MOLYBDENUM.

Methods of analyzing molybdenum ores, especially those of low grade, have been carefully studied by J. P. Bonardi, of the Golden station, and E. P. Barrett, now of the Salt Lake City station. The results will be published in a technical paper on "Determination of Molybdenum" now in press.

METALLURGY OF WULFENITE.

During the year, J. P. Bonardi finished work on the metallurgy of wulfenite and prepared a paper dealing with the best methods of extracting molybdenum and lead from wulfenite, giving an original method and the best conditions for the precipitation of molybdenum as calcium molybdate. This paper is published elsewhere."

Mr. Bonardi also studied the best conditions for the separation of wulfenite from barite minerals, and prepared a paper on the subject.

TUNGSTEN.

A bulletin entitled "The Treatment of Tungsten Ores of Boulder County, Colo.," written by Mr. Bonardi, of the Golden station, and J. C. Williams, of the Colorado School of Mines, describes the oredressing methods used in treating the ferberite ores of Boulder County, and the metallurgical processes used in connection with these ores.

PHOSPHORESCENT ZINC SULPHIDE.

Dr. Lind and C. W. Davis did considerable work on phosphoresent zinc sulphide used in connection with radium luminous paint. They studied the causes of luminosity in such paint and the reasons for changes in luminosity after the radium and the zinc sulphide are mixed.

"Bonardi, J. P., Notes on the metallurgy of wulfenite; Chem. and Met. Eng., vol. 21, Sept. 15, 1919, pp. 364-369.

VANADIUM INVESTIGATIONS.

CUPRODESCLOIZITE.

Cuprodescloizite, a lead, vanadium, and copper mineral, has never been treated commercially thus far in this country. J. C. Conley worked out methods for the treatment of the ore; the details were published elsewhere."

VANADINITE.

Vanadinite, or lead vanadate, was once treated on a commercial scale in this country, but without success. Mr. Conley made a careful study of the methods of treating this mineral, the results being published in a technical journal.

MONAZITE.

In cooperation with the General Land Office, Salt Lake City, N. J. Fibush, mineral examiner, made tests to determine whether certain lands in the Boise Basin should be classed as mineral lands. Electromagnetic separation of the materials concentrated from the monazite sands of the Boise Basin showed that the gold content alone of the sands would justify classifying the lands as mineral lands.

MINNEAPOLIS STATION.

GENERAL STATEMENT.

At the beginning of the fiscal year the entire staff of the station was engaged on war problems connected with the production and utilization of manganese. The following work was done:

MANGANIFEROUS IRON ORES OF THE CUYUNA RANGE.

T. M. Bains, mining engineer, assisted by G. E. Ingersoll, assistant metal-mining engineer, examined the manganiferous iron mines of the Cuyuna Range in Minnesota. The approximate duration of the work was seven months.

BENEFICIATION OF MANGANESE ORES.

Ore dressing tests of manganese ores from various localities throughout the United States were made by J. T. Norton, ore-dressing engineer, in cooperation with the school of mines experiment

a Conley, J. C., Treatment of cuprodescloizite for extraction and recovery of vanadium, lead, and copper: Chem. and Metal. Eng., vol. 20, pp. 465-469.

Conley, J. C., A proposed metallurgical process for the treatment of vanadinite for the recovery of lead and vanadium: Chem. and Metal. Eng., vol. 20, May 15, 1919, pp. 514-518.

station of the University of Minnesota. The work covered approximately eight months.

PRODUCTION OF MANGANESE ALLOYS IN THE BLAST FURNACE.

An investigation of blast-furnace practice for the production of ferromanganese and spiegeleisen by P. H. Royster, assistant physicist, assisted by F. B. Foley, assistant metallurgist, and R. L. Dowdell, junior metallurgist, occupied approximately eight months.

USE OF MANGANESE ALLOYS IN OPEN-HEARTH PRACTICE.

An investigation of the use of manganese alloys in open-hearth steel practice, by S. L. Hoyt, consulting metallurgist, assisted by F. B. Foley, assistant metallurgist, and R. L. Dowdell, junior metallurgist, covered about seven months.

JONES PROCESS.

Investigation of the Jones process for the direct reduction of manganiferous iron ore as a means of concentrating the manganese in such ore, was made by P. Christianson, metallurgist, and W. H. Hunter, metallurgical chemist, assisted by W. M. Sternberg, assistant chemist, and J. T. Jones, consulting engineer. The approximate duration of the work was three months.

BOURCOUD PROCESS.

Investigation of the Bourcoud process for direct reduction of iron ores was made by Messrs. Christianson and Hunter, assisted by F. H. MacDougall, physical chemist, and A. E. Bourcoud, consulting engineer. About two months were given to this work.

ANALYTICAL WORK.

Laboratory analytical work on steels, slags, and alloys, was done by C. E. Plummer, chief chemist, assisted in the course of the year by R. M. Winslow, W. J. Fullen, R. H. Hargett, junior chemists, and H. J. Livermore and J. H. Brennan, laboratory assistants. This investigation continued through the year.

LOW-GRADE GOLD ORES OF THE BLACK HILLS.

An investigation of low-grade sulphide gold ores of the Black Hills, S. Dak., by C. E. Julihn, superintendent, assisted by E. L. Smith, of the ore dressing department of the University of Minnesota, covered about three months.

140922°-INT 1919-VOL 1—49