January 28, 1915J 



NATURE 



5«7 



5000 separate memoirs have been examined page 

 by page. The substances are arranged in alpha- 

 betical order, and are also indexed according to 

 formulas. The references are indicated by num- 

 bers which correspond to the index of authors 

 given at the end of the volume. 



The book is well printed on good paper, and is 

 solidly bound in cloth. It is the only complete 

 work on the subject, and will be a valuable addi- 

 tion to English standard books of reference. 



J. B. C. 



OiSR BOOKSHELF. 



Boilers, Economisers, and Superheaters: Their 

 Heating Poiver and Efficiency. By Prof. R. H. 

 Smith. Pp. viii+128. (London: Crosby Lock- 

 wood and Son, 1915.J Price 75. 6d. net. 

 The author's purpose m this book is to provide 

 material whereby the designer of steam boilers 

 may t.ake account of the transmission of heat by 

 radiation from the incandescent fuel and the in- 

 candescent parts of the flame in as full and 

 scientific a manner as the data at present available 

 makes possible. It is assumed that combustion 

 is completed within, or close to the surface, of the 

 mass of coal, and that the heat so produced is 

 divided between heating the solid coal and heating 

 the generated gases. This assumption enables 

 the furnace gas temperature to be calculated for 

 various ratios of air actually admitted to th6 

 furnace to the air required by chemical theory, 

 and for various heating values of the fuel. The 

 result indicates that the temperature depends 

 almost solely upon the air ratio, and to a minute 

 degree only upon the heating value of the coal. 

 The heat given up by the gases passing alo^ig 

 the flues is then dealt with and similar calculations 

 are given for economisers ; applications to super- 

 heaters form the subject of a separate chapter. 

 The laws of heat transmission in boilers are too 

 complex for ready use in engineering drawing 

 offices, and the author has reduced these laws to 

 the form of diagrams. It is unfortunate that 

 these diagrams, while showing the way in which 

 the quantities involved vary, are reproduced to 

 a scale too small to be read accurately ; the reader 

 interested in boiler design is invited to purchase 

 copies of the original large-scale diagrams. There 

 is a great deal of interesting and useful matter 

 in the book, but it is not presented in a very- 

 readable form, and the practical designer is likely 

 to consult the diagrams much more frequently 

 than he will refer to the text. 



Through the Grand Canyon from Wyoming to 

 Mexico. By E. L. Kolb. Pp. xix + 344. (New 

 York : The Macmillan Co; London : Macmillan 

 and Co., Ltd., 1914.) Price 85. 6J. net. 

 This is a graphic but unassuming account of one 

 jf the very few successful descents through the 

 :ountry of the Grand Canyon by boat from end to 

 ;nd. For European readers it should have con- 

 rained a map, to ensure the appreciation of the 



NO. 2361, VOL. 94] 



vast distances involved and the remoteness from 

 civilisation of the plateau-heights on either hand. 

 Anyone who has travelled along gorges, such as 

 the Bosnian canyon of the V'rbas, will realise the 

 effect of a sudden contact with the outer world, 

 where some trail descends by a gentler part of 

 I the valley-side, finds a passage across the river, 

 j and climbs again to the upper air. Such episodes, 

 leading to the visiting of ranches where pioneers 

 I and outlaws still lead unhampered lives, broke the 

 long series of hazards which the fearless author 

 and his brother set before themselves. Xo two of 

 the cataracts are alike, and the tale is so well told 

 that the reader feels himself limited by rock-walls 

 4000 ft. in height ; he sees the huge fallen blocks 

 that seem to bar the passage, the spray rising 

 from some swift descent ahead, the fierceness of 

 which cannot yet be adequately gauged ; he feels 

 the whirl of the water round him in the rapids, 

 where the boat twists like a porpoise in green 

 waves; and at the end, among the sand-b.ars and 

 marshes close to Needles, after a hundred-and-one 

 days of travel, he takes leave of his guides with 

 a genuine and affectionate regret. 



The brothers Kolb are professional photo- 

 graphers, as the fine illustrations in this book 

 so amply testify. The famous journey of 

 J. W. Powell in i86g is, of course, fully .acknow- 

 ledged, and references are given to Stanton, Gallo- 

 way, Stone, and to the nameless trappers or 

 prospectors who are known to us only by shattered 

 boats or bleaching skeletons in the gorge. The 

 geological study of the district has aptly influenced 

 \Ir. Kolb's descriptions, and seldom has a great 

 adventure, carried out with skilled endurance, 

 been told so simply and with so fine an absence 

 of self-regard. Gresville A. J. Cole. 



Pumping hy .Compressed Air. By E. M. Ivens. 

 Pp. vi-f-244. (New York: J. Wiley and Sons, 

 Inc. ; London: Chapman and Hall, Ltd., 1914.) 

 Price 125. 6d. net. 

 In compiling this book the author has had the 

 advantage of being able to draw on considerable 

 practical experience derived from installing and 

 testing air lifts operating under a wide range of 

 conditions. Very good and clear descriptions are 

 given of various types of displacement pumps, 

 return air systems, air lifts, and pumping systems 

 generally. Of particular interest are the sections 

 dealing with the air lift. In this system a long 

 vertical pipe is led down the well, and has an 

 open mouth near the bottom and under the water- 

 level, so that normally the water stands at a con- 

 siderable height inside the pipe. Compressed air 

 is led down the well by a separate pipe, and is 

 discharged through suitably shaped orifices into 

 the first-mentioned pipe at a point well below 

 normal water-level. The ascending bubbles of air 

 cause an upward flow of water, which is finally 

 discharged into a tank at or above ground-level. 

 The theories of Harris and of Lorenz regarding 

 the action in air lifts will be found in the book, 

 together with much matter of practical interest. 

 The practical treatment is good, and forms a 



