Engineering Symbols
The Committee on Technical Nomenclature, of which John T. Faig, Professor of Mechanical Engineering at the University of Cincinnati, is Chairman, appointed by the Society for the Promotion of Engineering Education, has recently issued a report advocating uniformity in the use of symbols to designate engineering and mathematical terms: The selection of the symbols was […]
Lead Refining Process
The building is a lofty, well-ventilated one of hardwood frame, with galvanized-iron walls and roof, and consists of five spans running north and south, covering a total length of 230 ft. Each span is composed of nine bays of 13-ft. centres, making the total width of the building 117 ft. The refinery is situated conveniently […]
Precipitate Refining Method
This cyanide precipitate is unique in that it is apt to vary widely in composition in the course of very short periods of time, and a method of refining and melting that would prove highly satisfactory at one cleanup would yield almost a hopeless “mess” at a second. Table I gives a general conception of […]
Diastrophic Theory
The writer has devoted a number of years to practical operations and to the study of geology in the oil fields. In consequence, he has been brought to investigate the theories advanced to account for the accumulation of oil and gas in commercial deposits. It is the result of these investigations and his personal conclusions […]
Manganese Steel Rails
Since the writer has been intimately connected with the development of manganese steel for many years, some remarks upon the early work with regard to the rolling and forging of this material might be of interest, and particularly as to the question of rails of special quality and of superior wearing qualities. In a paper […]
Ammonia Carbon Dioxide Process
Most metallurgists appreciate the great need of a process for the extraction and recovery of valuable metals from complex ore, where the presence of one metal increases the cost of extracting the other metals to such an extent that not any of the metals can be extracted at a profit. We need only refer to […]
Grab Sampling in Mining & Drilling
Grab sampling usually consists in taking portions of ore at random from muck piles, chutes, or the tops of cars of ore. When done in this manner it is a haphazard method that can be relied upon only for roughly approximating the grade of the ore and often is employed merely for that purpose. The […]
How to Subsample a Large Bulk Sample or Soil, Ore, or Rocks
Before assaying, original samples must be cut down, often in several stages. Each cut involves, in effect, the sampling of a sample, the final portion comprising only the ore that actually goes into the crucible or flask and upon which the actual determinations are made. In cutting down samples to reduce the bulk to the […]
Mining Animation
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Sampling of Gold Bullion for Quality Control – Elemental Analysis
At the Seventh International Congress of Applied Chemistry I presented a paper, The Assay and Valuation of Gold-Bullion, in which are briefly mentioned a few illustrations of different methods of sampling gold-bullion, particularly cyanide-bars. Since then I have carried on an extensive investigation upon the sampling of gold-bullion in relation to its effects upon the […]