CUTTING SPEED IN FT. PER MIN.

12. Increased Output. Owing to its many advantages, but especially on account of clear head room for crane service and convenient speed control, it is found that the output of manufacturing establishments is in most cases materially increased or the running expenses correspondingly decreased by the introduction of electric motor service.

FIG. 10.

Curves showing length of time required to perform certain machine work with electric and mechanical drive.

If a factory or a plant manager contemplates the substitution of electric drive for the ordinary mechanical drive, or other method o. power distribution, it would be advisable for him to study carefully the requirements of his work, so as to determine if variable speeds are necessary and what ranges, if individual or group drive would answer, and which type of motor is best suited for each tool or machine to be driven. He should then tabulate the advantages derived and give them their true monetary value; against these he should balance the interest on the additional expenditure, the maintenance and depreciation items. If then the result shows an annual sav. ing which would amount to a sum of 5 per cent. or more of the cost of the new equipment, or the saving of a reasonable amount in the cost of his finished product, it would be a good policy for him to make the change. *

*The electrotypes for illustrations were loaned by the following companies: The Bullock Electric Mfg. Co., The Crocker-Wheeler Co., The General Electric Co., The Northern Electrical Mfg. Co.

ALUMNI AND UNIVERSITY NEWS.

SUMMER SCHOOL OF MINING.

A new departure was made this year in the conduct of the Summer School of Mining. Heretofore the class has always gone in one body to the mine or mines selected by the department and, in charge of from two to four instructors, according to the number of students, has done its work under constant supervision and advice. Last spring it was decided to divide the greater part of the class into small parties or squads, and send them without instructors to a number of different mining districts. To carry out this plan considerable correspondence was necessary in fixing upon mines suited to the purpose and in securing privileges and fa ilities for study. Through the liberality and kind coöperation of managers and superintendents, satisfactory arrangements were made at the following properties: Arizona Copper Co., Clifton, Ariz.; Daly West Mine, Park City, Utah; Tennessee Copper Co., Isabella, Tenn.; Baltic and neighboring copper mines, Houghton, Mich.; Penn Iron Mining Co., Norway, Mich.; Copper Queen Mining Co., Bisbee, Ariz. Twenty-one students, in six squads, elected to visit these mines; four squads of four men each, one of three men, and one of two. In addition, eight students made acceptable arrangements for themselves at various mines in or near Leadville, Ouray and Cripple Creek, Colo.; Butte, Mont., and Grass Valley, Cal.; also five students secured positions for the entire summer at mines in Tennessee, Michigan, Wisconsin, Colorado, and Arizona.

It was deemed advisable to retain the regular summer school in charge of instructors for such students as for any reason might prefer it. Arrangements were accordingly made at the Richard and Hurd iron mines, near Dover, N. J., and at several Pennsylvania anthracite collieries, in Luzerne Co., and the vicinity of Wilkes-Barre and Scranton. Seven students, constituting the remainder of the class, elected to attend this session, the work of which lasted from June 21 to August 3, inclusive, 41⁄2 weeks being spent at the iron mines and 11⁄2 week in the coal regions. The total number of students engaged in the summer mining work was 41. Each student of the squads which did independent work was provided with a twenty-eight page printed outline of work, a vade mecum containing such detailed instructions as would enable any earnest student to do all that is required of those who attend the session under the care of instructors This pamphlet is an amplification of the brief printed scheme heretofore gotten out each year for the summer school classes. It contains notes and suggestions on: "Outfit for the Trip," "How to Take Notes and Make Sketches," "Hand and Machine Drilling," "Blasting, Stoping, Development and Method of Working," "Handling and Transporting Ore," "Mine Car, Cage, etc.," "Timbering," "Shaft Sinking," "Drainage and Pumps," "Ventilation and Lighting," "General Surface Plant," "Hoisting Engine," "Gallows Frame," "Compressors," "Boiler Plant,' Shops, Ore House and Pockets,' "Hardling Men and Organization," Supplies and Material," "Geology and Ore Deposits," Milling and Concentration."

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The change in the mode of conducting the summer school work was prompted by several considerations which have been impressed by experience upon those of the staff of the School of Mines who have had charge of the work for some years past. In making satisfactory arrange. ments for the summer school work difficulties are often encountered which naturally increase with the size of the class. The mere matter of securing suitable living accommodations in small mining camps not infrequently constitutes a problem in itself; and the embarrassment incident upon handling parties of students underground in such a way as to afford proper opportunity for observation and study, and yet not interfere with the mine work and incur criticism from the mine officials, may be serious when the numbers are large. It becomes necessary to divide the class into squads of two, or at most four, students, and distribute them in different parts of the workings. When the class is small the conditions are ditferent. A sufficient number of suitable working places are readily found, so that a given party of miners would probably have but one squad of students stationed near them during the whole session. The miners are interested in the novel operations of note-taking and sketching, and are pleased to answer questions and offer suggestions. With small classes the total hindrance to the work of the mine becomes negligible. Evidently, a class consisting of but a single unit or squad- of say four students — would be most welcome to both manager and miner.

The question now suggests itself: what of the efficiency of the students' work under the new plan, without the oversight and assistance of instructors?

The writer has examined the note-books of the 34 students who were sent out this year without instructors and having to guide them only the printed outline of work above mentioned, together with such assistance as was given by officers and miners. He also spent about three weeks with the regular Summer School class, reading and criticising their notebooks every night. As a result, it may be stated that the average work of the independent squads is at least equal to that of the regular class. Expressed more broadly, this summer's work, carried on under the new conditions, appears to be fully up to that of the past twelve years.

By the constant attendance of instructors in the Summer School work as usually organized, time is economized to some extent; the instructor acts as a cicerone to the best of his ability, shows the student how to carry on his work, and gives him specific information. The good students realize that they are working primarily for themselves and not for the School of Mines; all they require is the entrée to the mine and the privilege of studying it. But, on the other hand, the poorer students may come to depend too much on the instructor, whose presence tends to relieve them of a salutary feeling of personal responsibility for the quality of the work done. This matter, and the question of the real effect of the marking system, merit further consideration.

Though there are as yet insufficient data at hand to judge conclusively of the effect on the independent squads of absence of regular note-book criticism, it seems reasonable to infer that the inefficient students of whom are to be found in every class lacking their daily gauge of quality, would be urged by fear of final failure to do better work.

some

There is a saving of time under the system of daily instruction and guidance, in view of which a longer period of summer work is required

from the students of the separate squads. Notwithstanding the likelihood that mistakes will be made, it is quite possible that more deliberation and a slower speed of work will be found advantageous. Provided with valuable privileges, for the proper use of which they themselves are responsible, the students may be led to a more thoughtful habit of work, accom. panied by the development of a spirit of investigation in keeping with university ideals.

Another consideration of a wholly different nature may be mentioned incidentally. When visiting the mines in small parties of three or four, the students have better opportunities to become personally acquainted with superintendents and foremen, and their chances are greatly increased of securing positions ready to be occupied immediately after graduation. An intelligent student could not fail to perceive that the quality of his work would be his recommendation.

DEPARTMENT OF CHEMISTRY.

General. The course in chemical engineering, as outlined in the QUARTERLY for April, 1905, has gone into effect with the opening of the current term. Since only the first year was offered for 1905-6, it was necessary to refuse all applications for advanced standing in chemical engineering from graduates of other institutions or students in other courses of applied science. The number of such applications, together with the actual enrollment in the first year class, is very gratifying and shows the existence of a distinct demand for a course of this character.

Summer Session. — Attendance upon the chemistry courses in the summer session continues to increase. The registration in chemistry for 1905 was 156. A course on the principles of chemistry has been substituted for the teachers' course formerly given and courses in elementary organic chemistry, organic and sanitary analysis, and the chemistry of nutrition have been added.

Analytical Chemistry and Assaying. Since the last publication of notes from these laboratories (November, 1903) Mr. M. A. Lamme has resigned as assistant to become tutor in mineralogy, and Mr. M J. Falk to enter commercial work. Mr. A. J. Mettler has been appointed assis tant to succeed Mr. Falk.

Professor Miller has been promoted to a full professorship; Drs. Wells and Sherman to adjunct professorships; Mr. Cruser to the position of lecturer in qualitative analysis. Professor Wells was granted leave of absence for the year 1905-6.

Professor Miller has taken charge of qualitative analysis and has reorganized the system of instruction. The regular class is divided into six sections. Mr. Ellard, Dr. Beans and Mr. Cruser each instruct two of these, while Dr. Uhlig teaches a special section consisting chiefly of students entering with advanced standing. Dr. Beans has general supervision of the theoretical instruction and Mr. Ellard of the laboratory work. The method of instruction gives more time to recitations than formerly, and the division of the class is such that no section contain over forty students.

A room adjoining the industrial laboratory has been equipped for research work in analytical chemistry and provides suitable accommodations for two graduate students. Four candidates for the degree of Ph. D.,

taking thesis work with Professor Miller, are engaged respectively upon investigations of iodine titrations, the chromi-cyanides, the silver-platinum and silver-iridium alloys, and the double ferric phosphates.

The following investigations have been completed and published since the last notice in this QUARTERLY :

"The Reduction of Lead from Litharge in Preliminary Assays and the Advantages of an Oxide Slag." By E. H. Miller, E. J. Hall and M. J. Falk. Trans. Amer. Inst. Min. Eng., 34, 387.

"The Influence of Diet, Muscular Exertion and Loss of Sleep upon the Formation of Uric Acid." By H. C. Sherman. Jour. Am. Chem. Soc., 25, 1157.

"The Determination of Nitrogen in Food Materials and Physiological Products." By H. C. Sherman, C. B. McLaughlin and Emil Osterberg. Jour. Am. Chem. Soc., 26, 367.

"The Determination of Molybdenum in Steel and in Steel-making Alloys." By F. V. D. Cruser and E. H. Miller. Jour. Am. Chem. Soc., 26, 675.

"A New Separation of Thorium from Cerium, Lanthanum and Didymium by Metanitrobenzoic Acid." By A. C. Neish. Jour. Am. Chem. Soc., 26, 780.

"A Crucible Charge for Gold and Silver in Zinc Ores." By E. J. Hall and E. Popper. SCHOOL OF MINES QUARTERLY, 25, 355

"Changes in the Composition of some Ferrocyanides of Cadmium and Zinc after Precipitation.' By E. H. Miller and M. J. Falk. Jour.

Am. Chem. Soc., 26, 952.

"The Determination of Nitrogen in Organic Compounds." By H. C. Sherman and M. J. Falk. Jour. Am. Chem. Soc., 26, 1469.

"The Application of Bismuth Ammonium Molybdate to Gravimetric Analysis." By E. H. Miller and F. V. D. Cruser. Jour. Am. Chem. Soc., 27, 116.

"The Determination of Ammonia in Milk." By W. N. Berg and H. C. Sherman. Jour. Am. Chem. Soc. 27, 124.

"A Study of Methods for the Determination of Formaldehyde." By R. H. Williams. Jour. Amer. Chem. Soc., 27, 595.

"The Influence of Atmospheric Oxidation upon the Analytical Constants of Fatty Oils"- Second Paper. By H. C. Sherman and M. J. Falk. Jour. Am. Chem. Soc., 27, 605.

"Comparative Experiments upon Chemical Preservatives in Milk." By H. C. Sherman, A. W. Hahn and A. J. Mettler. Jour. Am. Chem. Soc, 27. 1060.

In addition to the above papers there have been published from the quantitative laboratory:

"An Index to the Literature of Thorium, 1817-1902." By C. H. Joüet. Smithsonian Miscellaneous Collections, No. 1374, in Vol. XLIV. "Quantitative Analysis for Mining Engineers." By E. H. Miller. The Van Nostrand Co., 1904.

"The Calculations of Analytical Chemistry - Third Edition, Revised and Enlarged." By E. H. Miller. The Macmillan Co., 1905. "Methods of Organic Analysis." By H. C. Sherman. The Macmillan Co., 1905.

Organic Chemistry.

During the past year, the following gifts have been received: From Kuttroff, Pickhardt & Co., two pounds of uranine,