52 



NA TURE 



[May 19, 1904 



should have been told that the only thing to do was 

 to prohibit entirely uninsulated wires of any kind from 

 crossing below the telegraph wires. Why should the 

 telegraph wire be banished underground rather than 

 the overhead equipment changed to the conduit system 

 which Mr. Rider has shown us can be so efficient? 

 We fancy the objection which would be made to the 

 change by either party would be the same — that they 

 would prefer the other side to make it and to pay for it. 

 The ancient recipe for cooking a hare applies with 

 particular force to the design of a system of electric 

 tramways ; the motto of the tramway engineer should 

 always be " First catch your passenger." One cannot 

 read this, or, indeed, any comprehensive book on 

 electric traction, without being strongly impressed by 

 the degree to which the whole of the engineering 

 depends ultimately on the halfpenny passenger. The 

 engineer builds a bridge, dams a river or constructs 

 a railway from the Cape to Cairo, and the work is a 

 piece of engineering almost pure and simple, but he 

 may design and equip a first class traction system — 

 generating station, engines, dynamos, cables, track, 

 line and cars — and if he is out of his reckoning as to 

 the time the housewife goes to market all his energy 

 has been wasted. It is she who determines the kind 

 of car and the kind of service, and, these once settled, 

 everything else follows almost as a matter of course. 

 It is here really that electric tramways and electric 

 traction score so heavily ; they have the flexibility which 

 enables them to be designed to meet and to satisfy 

 the requirements of the public in a way which cannot 

 be done by the omnibus on the one hand or by the steam 

 railway on the other. The fact that electric traction 

 came into being when these other means of transport 

 were in strong possession of the field has been to its 

 own advantage ; it has had to cater for the require- 

 ments of the public in a way to attract them from its 

 rivals, and the success with which it has done so is 

 shown by the reaction on the railways, which are one 

 by one resorting to electrification as their only 

 salvation. 



Electric tramway and railway development in 

 England has been for a long time retarded from 

 various causes, but of late years it has been making 

 steady progress. Though much has already been 

 done, there is still a vast amount to do. Our large 

 cities all afford transit problems which it is safe to 

 say no other method of traction yet known can solve 

 so satisfactorily, and when these, as socially the more 

 pressing, have been tackled, the question of light rail- 

 way construction between town and town still offers 

 great fields for development. We have not here the 

 opportunities which the Americans possess but we 

 have problems of our own at once more difficult and 

 more urgent of solution. London in particular is a 

 case in point, and there can be no doubt that once the 

 Royal Commission now sitting has reported electric 

 traction schemes for London will be plentiful. The 

 electrical engineer who decides to go in for traction 

 work is certain before long of great opportunities ; he 

 cannot better prepare himself for taking advantage of 

 those opportunities than by reading Mr. Rider's book. 

 Maurice Solomon. 

 NO. 1803, VOL. 70] 



OUR BOOKSHELF. 

 Milk, its Production and Uses. With Chapters on 



Dairy Farming, the Diseases of Cattle, and on the 



Hygiene and Control of Supplies. By Edward F. 



Willoughby, M.D. (Lond.), D.P.H. (Lond. and 



Camb.). Pp. xii + 259. (London: Charles Griffin 



and Co., Ltd., 1903.) Price 6s. net. 

 All medical men and hygienists must necessarily 

 know something about milk and its production, and 

 this work, in a comparatively small compass, deals 

 very fully and adequately with the whole subject. The 

 author, being scientific adviser to one of the largest 

 of the London dairy companies, has had practical 

 experience in all branches of the subject, and his views, 

 therefore, are worthy of confidence. The first four 

 chapters are devoted to a consideration of the various 

 breeds of cows, the qualities of the milk they pro- 

 duce, and their housing, feeding, breeding, and 

 diseases. 



In the fifth chapter the legal aspects of diseases of 

 cattle are discussed, and a useful summary of the 

 " Diseases of Animals Acts " and of the " Dairies, 

 Cowsheds and Milk Shops Orders " is given. 



The important subjects of the elimination of tubercle 

 and the inspection and control of cowsheds are briefly 

 treated. The physiology and dietetics of milk, 

 pasteurisation and sterilisation, condensed, skimmed, 

 and separated milks, therapeutics of milk, koumiss 

 and other milk preparations, and diseases conveyed by 

 milk, all receive brief attention. 



The book concludes with chapters on the dairy, on 

 milk analysis, on control of adulteration, with 

 an abstract of the Foods and Drugs Act, and 

 on the bacteriological examination of milk. The 

 whole work is eminently practical and read- 

 able. As regards the conveyance of scarlatina 

 by milk, the well knqwn Hendon outbreak is 

 detailed, but no reference is made to Prof. Crook- 

 shank's researches, which throw considerable doubt on 

 some of the conclusions arrived at by the officials of 

 the Local Government Board. The author considers 

 that the alleged tendency to scurvy or scurvy 

 rickets in infants brought up on sterilised milk is not 

 proven, and with this we agree. It is stated (p. 142) 

 that Nuttall and Thierfelder failed to rear young 

 rabbits and fowls brought into the world under aseptic 

 conditions so that their intestinal tracts were free 

 from bacteria. This is not the case; Nuttall and 

 Thierfelder found that guinea-pigs (not rabbits) so 

 reared were even more vigorous than animals reared 

 under ordinary conditions. 



The book will prove a useful work of reference, 

 especially for medical officers of health, and the 

 numerous excellent illustrations add considerably to 

 its value. R. T. Hewlett. 



.4 Treatise on the Principles and Practice of 

 Dock Engineering. By Brysson Cunningham, 

 Assoc. M.Inst.C.E. Pp. xviii -t- 559. (London : 

 Charles Griffin and Co., Ltd., 1904.) Price 30^. 

 net. 

 The author of this book is on the engineering staff 

 of the Mersey Docks and Harbour Board, which has 

 control over the largest and most efficient system 

 of docks in the world. During the last few years, 

 under the direction of Mr. Lyster, the engineer-in- 

 chief, these docks have been modernised and brought 

 up to date. New deep-water basins and repairing 

 docks have been built; the entrances and sills of some 

 of the old docks have been lowered. Transit sheds 

 and cranes of modern type have been erected, so that 

 these docks are now able to deal with the largest class 

 of vessels yet built, and to load and unload the largest 



