November 27, 1902] 



NA TURE 



81 



was easily got by cutting slits in two pieces of tinfoil with a razor 

 and placing one over the other with the slits at right-angles, 

 while for a triangular aperture three strips of tinfoil placed so as 

 to leave just a tiny triangle open gave good results. 



G. H. Bryan. 



The Secular Bending of Marble. 



The fluidity of marble under pressure, of which Dr. See 

 mentions an instance in Nature (p. 56), has, I believe, been well 

 established by laboratory experiments. Another instance of 

 secular bending, similar to that quoted by Dr. See, was to be 

 seen in two alabaster slabs which formed the jambs of a door- 

 way in the Alhambra. Owing to the pressure brought to 

 bear on these by the settlement of the building, they had bulged 

 out from the wall by as much (if I remember right) as 6 or 7 

 inches. The slabs were about 7 feet long and a foot wide, 

 their thickness being, perhaps, a couple of inches. Whether 

 they are to be seen there st ill, or not, I do not know. 



Spencer Pickering. 



Summer and Winter. 



Concerning the relation of summer and the following winter 

 referred to on p. 63, a few facts from Greenwich records of the 

 last sixty-one years may be acceptable. We find this : — 



Summer warm, winter severe, 9 cases. 



., .. >, mild, 19 >> 



,, cold „ severe, 17 ,, 



» 11 ,, mild, 12 



(This leaves fourca^es with average values.) 



It thus appears that warm summers have been distinctly more 

 often followed by mild winters than by severe ones ; but the 

 difference in the other case, of cold summers, is less pronounced. 

 In this representation, wet is left out of account, the mean tem- 

 peratures of summer and winler being alone considered, and in 

 relation to the averages. But we might limit our attention to 

 summers that have been both cold and wet, as this last summer 

 has been. (Cold summers have not always an excess of rain. ) 

 Of such there appears to have been nineteen. Now taking all 

 those with a mean temperature under 6o°'5 (the average mean 

 temperature of summer below 6i°'2), I find that nine were 

 followed by severe winters and only three by mild winters ; 

 total, twelve. As the past summer comes in this group, the 

 chances seem in favour of a severe winter. A. B. M. 



Personal. 



I run not think it worth while to correct an error into which 

 the reporters of the ephemeral Press fell in prefixing the words 

 "his own " to the word *' work " in the account of my recent 

 speech at Liverpool, where I had said that my new sphere 

 afforded me a larger opportunity for work : simply. 



I do not know how best to correct it, or whether it is now 

 possible, but I see it has been reproduced in your University 

 Intelligence on p. 70, and an error incorporated in Nature is 

 of rather permanent character, and may be misleading to my 

 friends. Oliver Lodge. 



Birmingham, November 21. 



MATHEMATICS IN THE CAMBRIDGE 

 LOCALS. 



/^vN May 2g(vol.lxvi. p. 11 7), we announced an important 

 ^-^ change in the geometry of the Oxford local examin- 

 ations for 1903. Quoting from the notice which had just 

 been issued, attention was directed to the important state- 

 ment that " Questions will be set so as to bring out as far 

 as possible a knowledge of the principles of geometry, a 

 smaller proportion than heretofore consisting of pro- 

 positions as enunciated in Euclid. Any solution which 

 shows an accurate method of geometrical reasoning will 

 be accepted. No question will beset involving necessarily 

 the use of angles greater than two right angles. Geo- 

 metrical proofs of the theorems in Book ii. will not be 

 insisted upon." We have now received the schedules in 

 geometry that have been adopted for the Cambridge 



NO. 1726, VOL. 67] 



preliminary and junior local examinations in 1903. In 

 these, we are glad to see that the Cambridge Syndicate 

 has adopted to an even greater extent the reforms sug- 

 gested by the recent British Association Committee. 

 For the preliminary, junior and senior examinations : — 

 " Any proof of a proposition will be accepted which 

 appears to the examiners to form part of a logical order 

 of treatment of the subject. In the proof of theorems 

 and deductions from them, the use of hypothetical con- 

 structions is permitted " No schedule will be published 

 for the senior examination. The importance of the 

 schedules now published for the preliminary and junior 

 examinations will be apparent when it is considered that 

 they may be said to cover the work done by the boys and 

 girls in all secondary schools up to the age of sixteen 

 years, and the work of such older boys and girls as are 

 not trying for marks of distinction. Their influence is 

 great, and we heartily welcome the important change 

 that they place much greater stress upon observation, 

 measurement and experiment than on abstract reasoning. 

 It is to be observed also that there is no mere pretence 

 of accuracy : — " Every candidate must be provided with 

 a ruler graduated in inches and tenths of an inch, 

 and in centimetres and millimetres, a small set square, 

 a protractor, compasses furnished with a hard pencil 

 point, and a hard pencil." This mention of the hard 

 pencil is businesslike ; as soon as boys understand 

 that in their measurements of lines they must not 

 make errors of even one-hundredth of an inch, their 

 true scientific education begins. As for demonstra- 

 tive geometry, a great number of Euclid's propositions 

 are left out altogether. Books ii. and iv. have com- 

 pletely disappeared. Twenty-eight out of the forty-nine 

 propositions of Book i. have to be studied for the pre- 

 liminary and junior. Of the thirty-seven propositions of 

 Book iii., only ten have to be studied for the preliminary 

 and four more for the junior. Of the thirty-five proposi- 

 tions of Book vi., only thirteen are required for the 

 junior. The most important part of the geometry 

 examination is called practical geometry, and there is 

 every inducement to all teachers now to dwell largely on 

 experimental geometry, as all good teachers have done 

 for many years. 



We have reason to believe that in dealing with 

 arithmetic, algebra and trigonometry, the syndicate 

 will follow, as closely as it has done in geometry, 

 the recommendations of the British Association 

 Committee as drawn up by Prof. Forsyth. Should 

 this be so, we are assured of a very great reform 

 in the teaching of mathematics in all the secondary- 

 schools of England. This consummation will be 

 further assured by recognition of the reform, which 

 will surely come soon, on the part of the Civil Service 

 Commissioners and all other examining bodies in the 

 kingdom. We may say, then, that every average boy 

 looking forward to a career in the Civil Service, in 

 the Navy, in the Army, in any of the professions, will 

 have had an incubus lifted from his life, and a much 

 greater load will have been lifted from the spirits of his 

 father and mother. Boys susceptible of being crammed 

 for examinations will no longer have an unfair advantage 

 over their far wiser and more sensible but reputedly 

 stupid fellow competitors. There will, moreover, be a 

 chance that boys from schools will be able to take 

 better and fuller advantage of the instruction given in 

 technical colleges. 



To the educationist, the reform, however far-reaching 

 in its results, may appear small ; he may think that it 

 should have been effected long ago. This view, however, 

 does not in our opinion do justice to the services of the 

 reformers. It leaves out of account the strength of the 

 opposition. This reform needed that many men should 

 work in an unhopeful, heart-breaking way for it for many 

 years, and its importance is not diminished by its coming 



