6o8 



NA TURE 



[October 27, 1892 



root, but are "blocked" up the anterior root, and 

 diminished down that root. But in the inferences qua 

 functional impulses derived from these data, two con- 

 siderations appear to have been insufficiently borne in 

 mind — (i) The rapid death of interrupting grey matter as 

 compared with the endurance of white matter, and (2) 

 the disproportionate magnitude of negative variations by 

 electrical ^yiCv^dXxow as compared with negative variations 

 by functional excitation. The contrast between inter- 

 rupted and non-interrupted tracts, as regards the 

 transmission, gauged electrically, may have been in 

 part due to the first cause, and an adequate recog- 

 nition of the second fact would have withheld 

 Prof. Horsley from expressing astonishment — " a reve- 

 lation to us" is his phrase — at finding the elec- 

 trical variation in a nerve eight or ten times as great by 

 direct electrical excitation as by discharge of a nerve 

 centre. Du Bois-Reymond's analogous deflections 

 obtained on strychninized frogs were 1° to 4° versus 40° by 

 direct electrical excitation. A functional discharge down 

 posterior roots, if proved to occur, is a new and sur- 

 prising phenomenon ; but its existence is not at present 

 proved by the existence of an electrical discharge ; elec- 

 trical efifects by electrical excitation are tainted evidence, 

 electrical efifects down the posterior roots by functional 

 excitations above, although incidentally touched upon, 

 were not exhaustively examined, and considering the 

 recognized dangers of experimental fallacy, we may not 

 admit as proved that nervous impulses are discharged 

 down afferent channels. Prof. Horsley infers unre- 

 servedly that functional discharge occurs down the 

 posterior roots, and that centripetal impulses up the 

 anterior roots are blocked at the cord. This he 

 regards as striking evidence of the truth of the kinaes- 

 thetic doctrine {j.e., that nerve action starts from the 

 afiferent or sensory side of the nerve centre, p. 170) ; 

 but the connection between this presumed functional 

 downflow in afiferent channels and kinsesthesis is not 

 made apparent ; up-flow in afiferent channels is matter of 

 common knowledge ; up-flow by efferent channels has (so 

 far as we know) been contended for by no one since 

 Lewes. But as regards these last points, they may be 

 expected to receive fuller and more precise analysis in 

 the promised volumes on the brain and on physiological 

 psychology. A. D. W. 



ELECTROTECHNICAL TRAINING. 

 Electrical Engineering as a Profession and How to Enter 



It. By A. D. Southam, (London : Whittaker and 



Co., 1892.) 

 'I *HIS book consists of a collection of extracts from 



^ the notices of various firms regarding apprentices 

 and articled pupils, and from the prospectuses of colleges 

 which give an education in electrical engineering. It 

 reminds us of the gorgeous but depressing volumes one 

 has met so often in one's summer outing, containing par- 

 ticulars of hotels in Aden, hotels in Algiers, hotels in 

 Andermatt, &c., each hotel possessing, at least so it is 

 said in the gilt-edged page advertisement, every possible 

 attraction — a magnificent view, a first-rate cuisine, electric 

 light, ascenseur, and all the other dreariness of a 

 bandboxy barrack. 



NO. 1200, VOL. 46] 



First we thought that the length of description which 

 the author had given to a particular technical educational 

 establishment was a measure of its goodness, but that 

 idea we dismissed when we found that only three pages 

 of description were given to that technical college i n 

 South Kensington, regarding which the author says : 

 " This institution deservedly stands at the head of all the 

 technical institutions in this country." Next it occurred 

 to us that the author might have acted on the " good wine 

 needs no bush" principle; but that hypothesis had ta 

 follow the other, for we feel sure that the Walker 

 Engineering Laboratory at Liverpool is not bad, and 

 yet it requires fifteen pages of talking about. Then 

 we wondered whether each professor had been asked 

 to write as much as he liked, so that the length of 

 the description of a particular set of laboratories was ir» 

 proportion to the leisure of the writer ; and lastly, we have 

 been speculating whether the likeness to the " Hotels of 

 the World" book might not be quite complete, and the 

 length of the description was a measure of the length 

 of the purse of the advertiser. 



However, be the plan of the compilation what it may,, 

 the book contains a good deal of information, also some 

 salutary advice with which we quite agree : — " Un- 

 doubtedly the best training for a young man entering the 

 electrical profession is to go through the course at one of 

 the technical schools or colleges, and then when 

 thoroughly grounded in the theory and having a general 

 idea of the practice of his profession, to be articled for 

 some months to a good firm of electrical engineers, where 

 he will be able to acquaint himself with the practical part 

 of his business as actually carried out on commercial 

 principles ; " and again, " if he then goes to both a Tech- 

 nical College and is also articled, it is advisable that the 

 former should precede the latter, for the reason that when 

 he is placed iji the workshop his previous technical train- 

 ing will enable him to appreciate and see the importance 

 of much which he would otherwise have overlooked." 



For the fathers who desire to place their sons directly 

 in a works on leaving school, there is given a long list 

 of engineering firms who are willing to receive ^300 and 

 the lad ; some are willing to take only one hundred an! 

 twenty guineas a year, from year to year, or even as little 

 as ^100 a year — and the lad. In many cases a month's trial 

 is allowed, but judging from the ignorance of elementary 

 mathematics and science displayed by many articled 

 pupils in works, we presume that either these subjects 

 are not required, or a month is not a long enough time for 

 this astonishing ignorance to be discovered. Naturally 

 enough these firms do not bind themselves to provide 

 work for these articled pupils when their term is finished ; 

 indeed we know of a firm with over 100 articled pupils 

 which is applying elsewhere for an assistant. 



When will the parental idea die out that a lad who is 

 pitchforked into a works must turn out an engineer? No 

 doubt many of our successful engineers never received 

 any education in a technical college ; so many of our 

 battles were won by men armed only with bows and 

 arrows, but that is no reason for confining the equipment 

 of a modern regiment to these primitive weapons. Either 

 the teachmg given at a technical college materially helps 

 the lad in his subsequent practice in the works, or it is a 

 fraud and ought to be stamped out. If it affords real help 



