An Elementary Text-Book of Coal-Mining

Abstract

THIS little book is, as its title expresses, a book dealing with the most elementary principles of coal-mining. It has obviously answered its purpose extremely well, and has suited the needs of those to whom it is particularly addressed, as is only too evident from the fact that it has reached its twentieth edition since its original publication twenty-nine years ago. It need scarcely be said, therefore, that the general arrangement and style of the work are beyond criticism, otherwise it would not have survived the rigorous test of experience through which it has passed. Any review of the work must therefore be based upon the nature of the revision to which it has been subjected. It may fairly be said that the labour of revising such a work falls under three main heads, namely, first to eliminate all possible blunders; secondly, to bring the work thoroughly up-to-date, and thirdly, to see that there is no ambiguity likely to puzzle the student. Unfortunately, it cannot be said that the revision stands the test under any of these three heads, and a couple of illustrative examples of shortcomings may be quoted under each. There are, for example, blunders in spelling, such as “Plainmeller”for “Plenmeller” and “Maudline” for “Maudlin.” Under the second heading we have such statements as that the deepest borehole in the world is that at Schladebach, which attained the depth of 956 fathoms. This was true once, but the deepest borehole in the world to-day is that at Czuchow, Rybnik, Upper Silesia, which has attained a depth of 7350 feet. Again, the statement that of centrifugal fans those most generally adopted are the Guibal, Waddle, and Schiele was true once, but is not true to-day. The only reference given to the Kind-Chaudron method of sinking in this country is its first application at Marsden, the far more important, instructive, and recent sinking at Dover not being mentioned. Under the third head we get such a statement as that when it is inconvenient to state work in foot-pounds as the unit of work a higher unit is adopted termed horse-power. The confusion between work and power, to which most students are prone, is one that should never be allowed to creep into a text-book, where the difference between the two standards should be very clearly explained. Again, in dealing with the thickness of tubbing, two formulas are given, one due to Greenwell an d the other to Aldis; an example is given of the use of the former, which is here worked out, giving a thickness of 119 inches; if the reviser had worked out the same example by the second formula here given, he would have obtained a thickness of 198 inches, yet no hint is given to tell the student that the two formulas do not agree, or to help him in any way to reconcile so grave a discrepancy.

An Elementary Text-Book of Coal-Mining.

By Robert Peel. Revised and enlarged by Prof. Daniel Burns. Twentieth edition. Pp. viii + 420. (London and Glasgow: Blackie and Son, Ltd., 1922.) 6s. net.