; 4 8 



NATURE 



[September 14, igi 1 



Examinations. 



Sir William Ramsay's outspoken criticism on the value 

 of examinations will be welcomed by many, but it is un- 

 certain whether the general public could tolerate the present 

 educational system in their absence. 



When the chemical department becomes the department 

 of chemical research, and the student realises that he is 

 receiving a training in such practice, examinations as con- 

 ducted in the majority of cases mav possibly lose their 

 present-day significance. 



While practical training remains based upon text-book 

 instruction, which hardly calls for anything more than 

 observation on the part of the student, examinations are 

 necessary. There is no other method of testing the 

 student's memory. 



Observation has been defined as " the performance of 

 what is prescribed." It is the chief factor in a system of 

 empiricism, but it cannot be expected to occupy this posi- 

 tion for all time in a programme dealing with experimental 

 investigation. It may be that a correct method of instruc- 

 tion has yet to be devised. 



Examinations lose their chief value when they fail to 

 supply the student with an estimate of the value of his 

 personal qualifications, enabling him to confirm his 

 original intention or change the direction of his life's 

 work while there is yet time. W. P. Dreaper. 



September 6. 



Habits of Dogs. 



I cannot answer Miss Everett's questions on this sub- 

 ject, but would like to "ask another." Is it known to 

 be a common thing for dogs to carry hedgehogs in their 

 mouths? I have a fox-terrier who amused himself in our 

 garden by making life a burden to a hedgehog until the 

 latter disappeared. He would not only roll the hedgehog 

 about with his paws, but must have carried it a certain 

 distance in his mouth, for one evening I found him in 

 triumph at the back door of the garden with his lips all 

 marked with pricks and bleeding, and the hedgehog lying 

 in a ball at the top of three rather steep stone steps twenty 

 or thirty yards from the summer-house where he lodged. 

 If this is a usual form of play with dogs, it is a curious 

 one - Walter Kidd. 



Heatherdown, Alum Bay, I.W., September 5. 



Miniature Rainbows. 



Your correspondent Mr. W. E. Hart may be interested 

 to know that magnificent rainbows, which appear to be 

 within easy reach, may often be observed inside water- 

 coohng towers, the necessary conditions being a fairly 

 heavy shower of the cooled water and an opening at one 

 side of the tower sufficiently high to let the sunlight 

 stream in over the observer's head. B. P. H. 



Newcastle-on-Tyne. 



Underpayment of Teachers. 



Mr. Hodgson's letter on p. 315 directs attention to a 

 case of underpayment of teachers in collegiate institutions. 

 Possibly the City of Bradford Education Committee would 

 argue that, as universities generally offer about 150*. a 

 year to lecturers, judging by the advertisement columns of 

 Nature, 60;. a year, with the privilege of earning a little 

 more in the evenings, is sufficiently liberal for the work 

 that they require. 



150/. is a good stipend for a youth for the first few 

 years after leaving college, or as a retaining fee for a 

 man who has private means; but is it fair to expect men 

 with _ high university qualifications, years of teaching 

 experience, and a record of original work, to struggle to 

 make both ends meet for the best part of their lives? 



Twenty years ago, a lecturer might reasonably expect 

 to become a professor or to branch out into technical 

 work; but at the present time there are not enough pro- 

 fessorships to divide among the many highly specialised 

 men who have taken up university teaching during the 

 past ten years, and a technical career must be commenced 

 on leaving college. 



The prospects of secondary teachers, though poor, are 

 better: those of elementary teachers are better still; while 

 NO. 2185, VOL. 87I 



none of them are so good financially as those of the boy 

 who leaves school at sixteen or seventeen and enters a 

 bank or an insurance office. 



Since for university teaching a man needs a long and 

 expensive training, must be a graduate with first-class 

 honours, and must be capable of original work, and since 

 many cannot hope to obtain professorships and the like, 

 the remuneration offered to such men is woefully in- 

 sufficient, and is likely in the future to cause students of 

 ability to avoid university teaching as a career. 



E. R. Mum. 



" Omori," Bitterne, Hants, September 8. 



RUBBER. 1 



THE Rubber and Allied Trades Exhibition and the 

 International Rubber Congress, held conjointly 

 and recently concluded, are doubtless responsible for 

 the simultaneous appearance of four books on rubber. 

 One of these is a welcome attempt, as its title im- 

 plies, to cover the whole range of the subject, and 



Fig. 1. — Jelutong Tree, showing improved method of 

 tapping. From " Rubber. 



Mr. Philip Schidrowitz is to be congratulated on hav- 

 ing produced a volume which should rank as a 

 standard work for some time to come. 



The first nine chapters, half the book, are of special 

 interest to the lay reader, and are based, as the author 

 points out in his preface, upon six lectures delivered 

 by him in 1910 at Finsbury Technical College. The 

 historical sketch in chapter i., and the two following 

 chapters on production and consumption, and the 

 general nature of the rubber industry, will be found 

 most useful. The notes on wild, and what the author 

 terms industrial rubbers, such as Guayule, Jelutong, 

 and Madagascar vine rubbers, suffer somewhat from 

 his lack of personal acquaintance with the actual 



' "Rubber." By Dr. P. Schidrowitz. Pp. xv+303. (London : Methuen 

 and Co., Ltd., 10.11.) Price ioi. 6rf. net. 



