April 26, 1900] 



NATURE 



607 



encounters no other resistance in the risirnr main or dis- 

 charge pipe, except that due to the friction of the ascend- 

 ing water. The amount of that resistance is a function 

 of the velocity of flow, the area in cross-section, and the 

 length of the discharge pipe, and is in no other way 

 related to the size of the pump. 



" The Kaselowsky system is similar to that of Messrs. 

 West and DarHngton, originated many years ago, and 

 developed in the last dozen years in the Scotch collieries 

 by Mr. Moore. The chief features in which it differs 

 therefrom are the use of accumulator pressure and a 

 very long stroke, admitting of considerable reduction in 

 the dimensions of the underground engine" (p. 340). 



Just before summing up in this way, our author has 

 filled two and a half pages with a description of 

 Kaselowsky's system, furnished by the Berliner Mas- 

 chinenbau Actien-Gesellshaft, which the says "may be 

 comprehensible." 



Moere and Kaselowsky both transmit power by means 

 of a forcing pump actuated by steam at the surface 

 through two pipes filled with water to a pumping 

 engine situate at the point in the mine from which 

 water is to be raised. In Moore's pump, the water in 

 each pipe moves first in one direction, and then in 

 the opposite direction, acting the part of a rigid rod 

 in its downward stroke, and the pumping engine in the 

 mine oscillates in exact synchrony with the water in the 

 pipes and with the forcing pump at the surface. Thus, 

 if there were no leakage of motor water, each pipe 

 would always remain filled with the same water that was 

 originally put into it. Neither the forcing pump at the 

 surface nor the pumping engine in the mine requires to 

 have any distributing valves. The principal objection 

 to this pump is that the pipes being subject to variations 

 of pressure, expand and contract alternately, so that 

 part of the stroke of the forcing pump, and consequently 

 part of the work expended in driving it, is lost. 



In Kaselowsky's pump, on the other hand, the motor 

 water flows in a closed circuit, descending in one of the 

 pipes and ascending in the other. The excess of pres- 

 sure in the former over that in the latter is created by 

 the forcing pump on the surface, and is expended in 

 working the pumping engine in the mine. Both the 

 forcing pump and the pumping engine are necessarily 

 provided with distributing valves. 



The pumping engine in the mine consists of two com- 

 plete engines and pumps fixed side by side on the same 

 bed plate, each of which actuates the distributing valves 

 of the other in exactly the same way as this is done in a 

 Worthington pumping engine. The accumulators to 

 which our author refers are three in number. Their 

 purpose is to prevent the occurrence of shocks in the 

 motor water when the distributing valves open and close. 

 The motor water, travelling from the forcing pump to- 

 wards the pumping engine, passes under the plunger of 

 the first accumulator just after it leaves the forcing pump 

 at the surface, under that of the second just before it 

 enters the distributing valve chest of the pumping engine 

 in the mine, and under that of the third just after it leaves 

 the same valve chest. They act exactly the same part to- 

 wards the motor water as an air-vessel does towards the 

 water discharged by a pump. 



The difference between Moore's pump and Kaselow- 

 NO. I 59 1, VOL, 6l] 



sky's is therefore a very wide one, and does not consist 

 in " the use of accumulator pressure and a very long 

 stroke," as we are so confidently informed. 



In the hydraulic and other memoranda we find : 



" Dia. of circle or cylinder 4-7854 = area." 



This must certainly be an oversight. 



The rules for finding quantities are very arbitrary, as 

 the two following examples will show, and no explanation 

 is offered as to how they have been concocted. 



Thus :— 



" Square of dia. in feet x five times the depth in feet 

 = gallons." 



" Square of dia. in inches = lbs. of water for 3 feet 

 long -r- 10 = gallons." 



Although the book is called "A Complete Practical 

 Treatise," there seems to be no good reason why the 

 hydraulic and other memoranda should have been 

 pitched upon such a low level as to appeal only to the 

 capacity of those who can do little more than read or 

 write. The School Boards and the Science and Art 

 Department, now Board of Education, have for a number 

 of years past been training many boys and men who are 

 destined to irresistibly supplant the rule-of-thumb class 

 for whom such rules were originally framed. The least 

 of these would scorn to have a set of hard and fast rules 

 thrust upon him without some kind of explanation, and 

 no writer of the present day can afford to ignore this fact 

 if he expects his work to be appreciated and to have a 

 permanent value. 



Mr. Michell's book is altogether-too voluminous. In 

 the first paragraph of his preface he strikes the key-note 

 that should have been his guide in writing it, namely : — 

 " Many of the engines in use when the work was first 

 published have, in the severe ordeal of underground 

 work, maintained their position as useful and effective 

 pumping agents ; others have failed, and are now only a 

 name in the chronicle of mine pumps." 



Thus, judging by the past, we may be quite sure 

 that many more of those now in use will likewise dis- 

 appear from the scene. If, instead of describing ^s many 

 pumps now in use as he could find space for, our author 

 had instituted careful inquiries to find out the most 

 economical and trustworthy amongst them, if he had 

 confined his attention solely to these, condensed his book 

 to about one-quarter of its present size, and embodied 

 a few leading formulae in their proper places in the text 

 for the use of the student and the educated man who is 

 now, and is also yet to come, he would have produced a 

 more interesting, readable and useful work than the one 

 now before us. 



We differ entirely from the views expressed by him to 

 the effect that " In collieries with plenty of refuse coal 

 and slack of no commercial value, much of it, perhaps, 

 worth only a shilling or two per ton, a small initial out- 

 lay rather than economy in working, and a plant that 

 occupies little space in the pit . . . " can ever be a con- 

 sideration of such great importance in the eyes of a 

 properly educated colliery manager as to determine hint 

 to adopt an uneconomical pump because of its cheapness 

 in first cost. Such a man would foresee that additional 

 boiler-power and additional labour for stoking the boilers 

 would be required to supply steam to the wasteful pump. 



