April 14, 1910] 



NATURE 



183 



The book is clearh- written, contains many interest- 

 ingf illustrations, and, when taken in conjunction with 

 Messrs. Bjorling and Gissing's work, forms a very 

 complete descriptive account of the peat industries. 

 Occasionally, however, the author, carried away by 

 his enthusiasm for the utilisation of peat, refrains 

 from directing attention to the more obvious defects 

 in some of the schemes put forward, and leaves the 

 capitalist in ignorance of facts which might materially 

 alter the latter 's relations to the projected industries. 



The many attempts made within the past ten years 

 to utilise our peat supplies have proceeded in three 

 main directions, viz. the conversion of peat into fuel, 

 the manufacture of power gas from peat, and the 

 utilisation of peat fibres for the manufacture of paper, 

 alcohol, moss litter, &c. 



The chief diflficulties attending the conversion of 

 peat into fuel on a commercial scale are the removal 

 of the large amount of water contained in freshlv cut 

 ot^at and the increase of the low specific calorific 



wer, i.e. the calorific power of unit volume, of the 

 iuel. The removal of the water by mechanical 

 methods (hydraulic pressure, centrifuging, &c.), and 

 also its removal by artificial heating, have been 

 shown again and again to be unremunerative, and 

 no process in which any of these methods forms a 

 constituent part can, with normal prices prevailing 

 for rival fuels, be regarded as economically sound. 

 The only method for removing the water which has 

 proved commercially successful is the method of air- 

 drying employed by farmers for the production of 

 their turf. 



The specific calorific power of turf can be increased 

 by converting the peat into press turf or into machine 

 turf, but the diflficulty of drying the product in a moist 

 climate like that of Ireland, and the high cost of 

 transport, render it unlikely that turf will displace coal 

 as a fuel from any districts other than those in the 

 immediate neighbourhood of peat bogs. 



The manufacture of producer gas and its employ- 

 ment in industries such as the fabrication of glass, as 

 well as the production of power gas and the recovery 

 of the ammonia simultaneously formed, may under 

 carefully selected conditions be made remunerative, 

 but peat cannot, under any conditions likely to arise 

 in the near future, become so cheap a source of energy 

 as coal at the pit-mouth in England. 



It is unlikely that the conversion of peat fibres into 

 paper or into alcohol will prove successful com- 

 mercially. From one ton of anhydrous, light, surface 

 peat, by hydrolysis about o'28 ton of reducing sugars 

 can be obtained, and if the latter were all fermentable 

 they would afford about forty gallons of alcohol. If 

 this were the average yield of alcohol from peat 

 the process would be very remunerative, but, un- 

 fortunately, about one-half the amount of sugars in 



drolysed peat consists of pentoses which are 

 . jt capable of undergoing saccharomycetes fer- 

 mentation, and consequently the yield of alcohol 

 rarely exceeds twenty gallons per ton of dry peat ; 

 if surface peat is not employed in the manu- 

 facture, the yield may fall so low as five gallons 

 per ton. If the yield of alcohol from a given speci- 

 NO. 21 1 1, VOL. 83] 



men of peat falls below sixteen gallons per top, the 

 manufacture of "peat spirit" will be unable to com- 

 pete with that of " potato spirit " owing to the greater 

 value of the by-products in the latter industry. The 

 peat moss-litter industry, on the other hand, is from 

 the commercial point of view the most flourishing of 

 all the peat industries, and is likely to prove as re- 

 munerative to the capitalist in the future as it has 

 been in the past. Hugh Ryan. 



THE HEALTH OF THE SCHOOL CHILD. 

 The Hygiene of School Life. By Dr, Ralph H. 

 Crowley. Pp. xiv + 403. (London : Methuen and 

 Co., 1910.) Price 35. 6d. net. 



IN his preface to this work the author states that 

 it was written while he was medical superin- 

 tendent to the Bradford Education Authority, and that 

 the conclusions arrived at and the measures advocated 

 are based upon his own practical experience gained 

 amongst the schools and school-children of that city. 

 He furthermore states that the views expressed receive 

 no added sanction from the fact that he now holds 

 an official position in the Medical Department of the 

 Board of Education. Although this may be so, it 

 seems as if his present position is responsible 

 (through the official non-committal attitude it has 

 engendered) for the one outstanding deficiency of the 

 book, namely, a lack of definiteness and of detail. 

 For instance, one who consults a manual upon the 

 hvgiene of school-life might reasonably expect some 

 definite directions upon the cleansing and disinfection 

 of school premises ; the measurements of seats and 

 desks for children in different age groups, with the 

 appropriate slope of desks for reading and writing 

 purposes ; the distances recommended between the 

 hanging-pegs of cloak-rooms ; but in these respects, 

 as in so many others, he will find but generalities. 

 Indeed, generally speaking, the work is sketchy, and 

 requires the addition of fuller and often more definite 

 information to become a useful addition to the already 

 voluminous literature upon the subject of school 

 hygiene. 



It need scarcely be said that the matter given 

 and the views expressed by one with the experience 

 and knowledge of Dr. Crowley are sound, and that 

 certain parts of the work reach a good standard of 

 merit; more especially is this true of the chapters 

 upon special groups of school-children. The chapter 

 upon medical inspection of the child in the school is also 

 very good, and it impresses upon the reader the fact 

 that medical inspection, and all that it involves, has a 

 part to play now and in the future, the importance 

 of which can hardly be over-estimated. As Dr. 

 Crowley states in his introduction, it is a service 

 which stands out clear and well-defined, demanding 

 of the medical men and women who perform it the 

 highest qualifications and attainments. While essen- 

 tially a part of the public health service, it is never- 

 theless a department which can never know its own 

 full development until it recognises itself as a part 

 of the whole public health service of the country', and 

 links itself up and has an organic relation with that 



