5^ 



NA TURE 



[Nov. 20, i ! 



erred), but makes us acquainted with new thoughts which 

 in themselves are worthy of pursuit, and which in their 

 present form are of general educational service. 



Karl Heun 



The Dynamo : How Made and How Used. A Book for 

 Amateurs. By S. R. Bottone. (London : W. Swan 

 Sonnenschein and Co., 1884.) 



This little book of 75 pages is designed to give to 

 amateurs practical information as to the construction of 

 a small working dynamo-machine. What is aimed at is 

 the building up of a machine capable of being worked by 

 hand and suitable for experimental purposes. The 

 dynamo-electric machine is one which an amateur 

 mechanician may very well undertake with every prospect 

 of success and satisfaction ; and the book before us is 

 thoroughly practical and is pleasantly written, and will, 

 we feel sure, be acceptable to many. We are acquainted 

 with books on the steam-engine for amateur constructors; 

 but a dynamo of simple form is easier to make than a 

 steam-engine, and will, we think, when made, prove a far 

 more useful and pleasure-giving toy than a steam-engine 

 such as an amateur can put together. When all is done, 

 a steam-engine of amateur construction can do little more 

 than go round and round ; but a host of experiments in 

 electric lighting and in electro-chemistry may be made 

 to follow on the successful completion of a small hand- 

 dynamo. 



The author describes the making of a very simple 

 dynamo with a kind of shuttle-wound armature. All his 

 instructions are clear and, as we have already said, 

 thoroughly practical. The only question on which we 

 have any doubt whatever is whether, at any moderate 

 speed of turning, the dynamo will yield so much current 

 as the reader is told he may expect. 



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Natural Science in Schools 



As one who has been engaged in teaching science in -schools 

 for the last ten years, I should like to make some remarks on 

 Prof. II. E. Armstrong's interesting lecture, published in Nature 

 of November 6 (p. 19). 



(1) In the first place I would like to express my agreement 

 with his weighty opening words. The main body of school- 

 masters are so completely without any science-training that it 

 is very difficult for many of them to see its necessity or even 

 its advantage. The younger generation of masters in the large 

 public schools, moreover, having come to the work in recent years 

 have not, like their predecessors at Rugby, Clifton, Taunton, and 

 elsewhere, had an opportunity of observing the gain of life and 

 general intelligence which followed the introduction of science 

 into the regular school work, in those schools where it was taken 

 in hand seriously and with enthusiasm. Others, again, have more 

 or less forgotten. Consequently it is still necessary to point out 

 that, excellent as is the training given by the mathematical and 

 classical teaching of our schools, yet that by itself it is not 

 enough. No excellence in the method of teaching classics and 

 mathematics will compensate for this, to adopt Dr. Armstrong's 

 words, that they fail to develop "the faculty of observing, and 

 reasoning from observation and experiment," that they fail 

 to give any idea in the concrete of the nature of evidence. No 

 doubt many able men educated on a classical or mathematical 

 basis, can observe and reason from observation ; this is, however, 

 in spite of, and not in consequence of, their training. To the 

 majority the deficiency is a serious matter, and probably it goes 

 far to account for the peculiar opinions of scholars one sometimes 



hears expressed by practically successful men, and produces the 

 unfortunately too prevalent idea among them that, if their sons 

 are to go into business and to succeed, they must not stay at 

 school too long —they must not learn too much book-learning. 

 It should, then, in addition to its other services, be the function 

 of science in education to keep awake and develop the natural 

 practical intelligence of our lads, and so to make up for the 

 deficiencies in this respect which accompany the otherwise vast 

 advantages of a literary and mathematical culture. 



(2) I suppose that no science-teacher will fail to agree with 

 Prof. Armstrong that we have by no means exhausted the possi- 

 bilities even of our present opportunities. As my object is to 

 advocate advances, however, I will not dwell upon that part of 

 his remarks except to say that I am sure a closer acquaintance 

 with the methods of a good many of our science schoolmasters — ■ 

 with the time at their disposal, the laboratories they work in, and 

 their boys, in short with the conditions under which they work — 

 would satisfy him of the considerable value educationally, when 

 it is properly done, of much that he condemns, and also that 

 something of what he advises is already being attempted. 



The lectures in schools are already, I should say, usually more 

 or less of the nature of the tutorial classes which he recommends, 

 and, whilst we recognise a great educational value in analytical 

 work, if properly taught, we shall, I feel sure, be ready to abandon 

 that for something better as soon as it is ready for us. 



Having said this much, I hasten to add that I quite recognise, 

 on the other hand, the value of Trof. Armstrong's suggestions, 

 and that I am at present conducting a class on a system which in 

 principle is very like that which he suggests. Indeed it is in 

 several important points the result of suggestions made to me by 

 Prof. Armstrong some two years since. More particularly I am 

 trying a form of what I may call the problem method of practical 

 teaching, which Prof. Armstrong so strongly recommends. 



As it is only lately that we have had the necessary accommo- 

 dation for this attempt, my experience is not very great. But I 

 have learnt a good deal, and, as Dr. Armstrong's lecture brings 

 the question into prominence just now, I may say what my 

 experience is so far. Remembering that economy of time is of 

 the first importance, and that our object in teaching science in 

 schools is to promote a certain attitude of mind towards Nature 

 rather than to produce skilful manipulators, I am not yet cer- 

 tain whether courses of work in which each pupil, with assist- 

 ance, suggests and carries out the experiments himself, or 

 tutorial classes, in which the suggestions are as far as possible 

 elicited by the teacher from the class, and then the work is 

 carried out by the teacher before the class, will give the best 

 results. I tried the latter plan some years ago with beginners 

 at Taunton with the most encouraging results. I believe, how- 

 ever, that a combination of the two methods will finally prove 

 best. There is no doubt that greater interest is created when 

 the pupils do the work themselves ; on the other hand, much 

 time is lost, at first, through difficulties of manipulation. 

 Accordingly I am trying to arrange things so that the simpler 

 experiments shall come together and be done by the boys ; and 

 when anything more difficult has to be done we fall back upon 

 the tutorial method. I have no doubt of the advantage of 

 practical work combined with some form of lecturing, if there is 

 lime enough. But in schools there rarely is time enough given 

 for both. As an introduction to a course of lessons on the present 

 system a practical course or a tutorial class on the lines proposed 

 by Dr. Armstrong will certainly be of great value, and one or 

 the other must, I think, be possible in almost every school. 



(3) I will now pass to some points not discussed by Dr. Arm- 

 strong in which it appears to me that chemical teaching at 

 present is open to improvement. I always aim, myself, not at 

 informing my classes of chemical facts or principles, but, as 

 far as possible, at leading them to discover them for themselves. 

 In this I am more or less hampered by the absence of sufficient 

 appreciation of the bearing of the simpler physical facts of Nature 

 upon chemical processes. This I supply as far as I can. But I 

 believe, and I am trying the experiment, that a real advance in 

 the value of chemistry as an education will be made if, as an 

 introduction, the beginners are put through a course of practical 

 problem work which brings out in every possible way the 

 dependence of chemical operations upon the simpler physical 

 properties of matter ; such as volatility, solubility, &c. 



(4) I was told the other day, by a great authority on educa- 

 tional matters, that science has had a distinct and good effect on 

 grammar-teaching. I think, on the other hand, that science- 

 teachers have been rather slow to recognise and imitate one 



