January 28, 19 15] 



NATURE 



589 



assertion that the offspring of wild males and tame 

 females tend to manifest the wild temper of their 

 fathers. 



It seems remarkable that nobody — so far as I am 

 aware — has hitherto directed attention to the passage 

 which I have quoted above. It occurs incidentally in 

 ;\ letter which described such novelties as the sperma- 

 tozoa and red blood-corpuscles of the frog, and the 

 ciliate Protozoa parasitic in the frog's intestine. But 

 it is perhaps even more remarkable that neither 

 Leeuwenhoek at the time, nor anybody else for some 

 two hundred years Subsequently, perceived the import- 

 ance of such obserxations as the rabbit-fanciers of 

 Holland had made. Leeuwenhoek was, of course, an 

 " animalculist " : and he cites the case of the rabbits 

 to confute ^'' non nemo Doctorum" — evidently an 

 " ovist " — and to " bring a sufficient proof of the fruits 

 coming from the Male seed, and the females only 

 contributing to the nourishment and growth of it." 



Leeuwenhoek's remarks evidently do not constitute 

 the earliest known reference to rabbit breeding. For 

 Darwin ("Animals and Plants," chapter iv.) gives 

 earlier references to Gerx^aise Markham (163 1), and 

 Aldrovandi (1637), which show that several kinds of 

 rabbit were already kept and bred at the beginning 

 of the seventeenth centur}'. Nevertheless, the passage 

 which I have quoted above is, perhaps, the earliest 

 exact account — based upon experiment — of the in- 

 heritance of any character in any animal or plant; 

 and as such I think it is worthy of record. 



I am indebted to my friend. Prof. R. C. Punnett, 

 F.R.S., for information on certain matters mentioned 

 in this letter; and I would refer the reader interested 

 in the subject to his important pap>er, -" Inheritance 

 of Coat-Colour in Rabbits," published in the Journal 

 of Genetics, vol. ii., No. 3, 1913, for further facts. 



Clifford Dobell. 



Imperial College of Science, South Kensington, 

 London, S.W., January 15. 



Books for Belgian Students. 



We are gradually building up a little Belgian L ni- 

 versity here for students who, for one reason or 

 another, cannot go to the front, and for professors 

 who are past the age of serving. Altogether we have 

 between one hundred and two hundred students, and 

 >ome fifteen to twenty professors. 



Last term we were able to establish effective teach- 

 ing in four faculties, and this term we have increased 

 the number to six. In the faculty of medicine we are 

 in need of copies of some standard text-book on 

 human anatomy — preferably Gray's. 



This L'niversitv' has already found several thousand 

 pounds to support our guests, and will have to find 

 several thousands more to keep things going until 

 next June. Consequently we have to husband our 

 resources very- carefully, and cannot afford to pur- 

 hase such expensive text-books as Gray's " Human 

 Anatomy." 



It may be that your readers have copies of this work 

 Iving unused on their shelves. If this is so, I should 

 be iTateful if they would send them to me for the use 

 of these students. At present ten or a dozen copies 

 w ould suffice. A. E. Shipley. 



Christ's College Lodge, Cambridge, January- .25. 



An Unexplained Laboratory Explosion. 



I SH.\LL be glad if any of your readers can give me 

 an explanation of the following occurrence. 



Owing to the fact that we are somewhat out of 

 |the way here, and, in consequence, fresh bleaching 



NO. 2361, VOL. 94] 



powder is difficult to obtain, I have found it necessary-, 

 when demonstrating the formation of chloroform, to 

 find some method other than the usual treatment of 

 alcohol with bleaching powder. 



\\'ith this object, a few days ago I prepared a 

 mixture of 60 grams of slaked lime with 400 c.c. of 

 cold water and 40 c.c. of alcohol. The mixture was 

 placed in a 2000 c.c. flask, through the cork of which 

 a long tube conducted chlorine to the bottom of the 

 liquid. Through the cork also went another short 

 tube connected to a condenser. 



Chlorine had been passing into the liquid fairly 

 quickly for about twenty- minutes, and the contents 

 of the flask had warmed up to perhaps 50° C, when 

 a slight smell of chlorine became evident at the end 

 of the condenser, together with a small amount of 

 white fumes ; but inside the big flask, except for the 

 slight rise of temperature, there was no evidence of 

 chemical action. Suddenly, with no warning what- 

 ever, the whole apparatus blew up; I might almost 

 say detonated, as there was not a piece bigger than 

 a sixpence left, either of the flask, the condenser, or 

 the small flask put to catch the distillate when it 

 should arrive. 



Owing perhaps to the violence of the explosion, I 

 got off with a few scratches on my face. My clothes 

 were cut by pieces of glass, however, and the frag- 

 ments were scattered for at least six yards all round. 

 There was no odour, either of chloroform or anything 

 else, apparent; only that of the chlorine from the 

 generating flask, which, curiously enough, had escaped 

 injur}-. The whole deliver)- tube was intact, and also 

 the exit tube from the big flask, the neck of which, 

 with the cork, was left sticking in the clamp, so that 

 I was able to be sure that the trouble was not due to a 

 blocking up of the exit. W. F. A. Ermex. 



O. Granber}-, Juiz de Fora, Minas, 

 December 11, 1914. 



Demonstration of Strain-hardening of Steel. 

 The accompanying photograph (Fig. i) represents 

 the side of a steel bar. The bar was first marked 

 by a punch in the way shown, and the punch marks 

 were afterwards completely filed out. The side was 

 then polished and the bar pulled in a testing machine 

 beyond the elastic limit of the material. The polished 

 surface was giadually destroyed everyw-here except 

 just under the punch marks, where the overstrained 



Fig. I. 



material retamed its polish and the marks again 

 became evident. In the strained bar the marks remain 

 distinctly raised above the rest of the sui-face. A 

 similar experiment was made with a shorter bar that 

 was afterwards subjected to compression along its 

 length. Again the punch marks became clearly 

 visible, but this time they remained as p>olished depres- 

 sions instead of raised surfaces. 



R. W. Ch.\pm.\n-. 

 The Universit}- of Adelaide, South Australia, 

 November 30, 19 14. 



