December io, 1908] 



A'^ TURE 



153 



creii want to be accomplished in the art of using tools 

 and producing results in the conventional way as 

 performed in the way of trade by the professional. 

 In the opinion of the writer of this notice, he ought 

 not to want, for in that case he is certain to sacrifice 

 his interest in the object for which he is preparing 

 something to the preparation itself; he will change 

 from the experimentalist to the amateur mechanic. 

 He must, if he will retain his role as experimentalist, 

 learn to be ruthless, and, if necessary, to do brutal 

 things and defy every convention, so long as he 

 attains his object. The author expresses this idea 

 more neatly as follows : — 



" The craftsman will doubtless find humour in some 

 of the suggestions put forward herein, but it should 

 be remembered that we are first of all teachers, and 

 that we must use skill in craftiness in order to over- 

 come our lack of the craftsman's skill. These are 

 methods that will serve our purpose, and they are 

 within our resources." 



Was not the same idea expressed by the great 

 Fresnel nearly a century ago in words such 

 as these : — " If you cannot file with a saw or 

 saw with a file you will be no good as an experi- 

 mentalist " ? 



Wood-work, metal-work, and glass-work are the 

 subjects of the first three divisions of the book, and 

 these are supplemented by one called general, in 

 which sixteen diverse subjects are treated, and these 

 are followed by three appendices and an index. It 

 would be tedious, and it would serve no useful purpose, 

 to go through these chapters seriatim. It is suffi- 

 cient to say that the descriptions are clear and are 

 well illustrated, and that the book will be a valuable 

 if not an invaluable addition to the working library 

 of every physical laboratory. While commendation 

 is justly earned by the author, there are a few points 

 to which the writer would direct his attention in the 

 hope that they may assist him in the preparation of 

 the second edition. 



In the section dealing with grinding and sharpening, 

 the use of emery or carborundum wheels for grind- 

 ing, or of artificial hones made of these materials for 

 sharpening, is not suggested. The writer would 

 urge that the natural stones have been superseded ; 

 he would be glad to know the experience of others 

 with a slab of aluminium as a hone for the produc- 

 tion of a fine edge. A solution of camphor in ter- 

 pentine is, as is usual, recommended for use when 

 drilling glass. The writer has always wondered what 

 the camphor is for and if it makes anv difference, 

 for a recipe of this kind is and always will be faith- 

 fully repeated in book after book even when useless. 

 Camphor dissolved in turpentine is used in making 

 certain tailed stars for rockets. Did a firework-maker 

 once lubricate a drill with the only turpentine he 

 could find and thus start the use of camphor? Prof. 

 Threlfall is most enlightening on the subject of drilling 

 glass in his book on laboratory arts. 



It i-; an omission to describe methods of cleaning 



mercury and ignore the existence of the vacuum 



still, which ought, in the writer's opinion, to be 



set up permanently in every physical laboratory. Simi- 



NO. 2041, VOL. 79] 



larly, it is an omission to describe a number of well- 

 known cements and ignore the existence of that most 

 useful addition to the resources of the experimentalist, 

 viz. the much advertised caementium. The writer has 

 used this material on all classes of substances, and 

 he considers it one of the most useful in the labora- 

 tory. He would mention incidentally that it does not 

 ruck up the end grain of soft wood, so that badlv 

 made patterns may be quickly smoothed over with 

 it and interior angles filled in without producing a 

 hedgehog back, as is the case with shellac varnish, 

 and giving rise to the necessity for much glass-paper- 

 ing. Soldering is described as practised with the tin- 

 man's "bit." This, it is true, is often, especially 

 with sheet work, exceedingly useful, but for nearlv 

 all the operations of the laboratory, especially when 

 thicker work in brass is to be put together, the method 

 known as sweating is preferred, and will be prac- 

 tised nine times while the bit is used once. The 

 process of sweating is not described, nor is there 

 given the very important direction to wash well and, 

 if possible, to boil everything that has been soldered 

 or sweated with chloride of zinc. Silver soldering is 

 the cleanest and neatest form of brazing, and it is 

 surprising that it is not more commonly practised. 

 The author's description appears to the writer some- 

 what meagre. The essential to success being a uni- 

 form low red heat, the process is much more easily 

 carried on in a fire bed or in a muffle than by a more 

 fierce and local source of heat such as a blowpipe. 

 Where this is used, every use that is possible should 

 be made of reverberation from pieces of firebrick to 

 maintain the heat uniform. 



The author rather lets himself go when he gets 

 to varnishing, staining, French polishing, and sand- 

 papering. Information of the kind is very useful in 

 its way, but if there is anything in which the student 

 should not be encouraged it is on the " beautifica- 

 tion " of his apparatus. Varnish or paint for pre- 

 servation are well enough when there is necessity 

 to preserve ; as a rule, experimentalists' apparatus 

 is made, used, and done with; it requires neither 

 benutification nor preservation. The results obtained 

 may be worth the latter. 



We would, in concluding this notice, refer to two 

 passages in the preface : — 



" The ability to ' fix up ' a piece of uncatalogued 

 apparatus, by which a point under discussion may 

 be proved, is worth the expenditure of time and 

 trouble in its attainment, but until now no systematic 

 attempt has been made in this direction, and it is 

 onlv through the organisation of summer courses 

 for science teachers in Ireland and Yorkshire that 

 the prospect of success is held out." 



And again : — 



" The result must be a quickening of interest on 

 the part of teachers able for the first time to con- 

 struct their own special apparatus." 



Has the author ever heard of the late Dr. Guthrie, 

 who instituted this identical work at South Kensing- 

 ton, and sent out into the country hundreds of science 

 teachers armed, it is true, with imperfect craftsman- 

 ship, but for all that able to " fix up " simple 



