I 



MM. Cahours and Hofmann on a new Class of Alcohols. 30^ 



under the microscope, and the embryos were visible even to the 

 unaided eye, I examined the whole number then remaining, viz. 405i~ 

 thus reduced, owing to 6/ having been removed, one after another 

 having become opaque, and 152 having been taken out for the pur*' 

 pose of experiments. Of these 405 remaining, 138 were found alivey 

 each containing a well-formed embryo, and 267, though still tran^-' 

 parent, without life, no marks of organization being to be seen in 

 them, either with the naked eye or under the microscope. Hence, 

 irrespective of the 152 experimented on, the proportion of living to 

 dead on the 14th of December would appear to be as 138 to 364, 

 or about 25 per cent. And, with the exception of two which died 

 after the 14tb, all those then alive were hatched, the first on thm 

 31st of the same month, the last on the 9th of January. ! s^*::^?- 



What are the conclusions to be drawn from these results? Froni 

 those of the first series of experiments, may it not be considered as 

 proved that the power of resisting an undue increase of temperature 

 is possessed in a higher degree by the ova in an advanced than in an 

 early stage of development, — the degree probably being in the ratio 

 of the age? From those of the second series, is it not as manifest 

 that the power of bearing distant transport, and of retaining life in 

 moist air, is in like degree increasing with age ? And from both, 

 may not the general conclusion be drawn, that the strength of vi- 

 tality of the impregnated ovum, or its power of resisting agencies 

 unfavourable to its life, gradually increases with age and the progress 

 of foetal development ? And as the Charr is one of the most delicate 

 of the family of fishes to which it belongs, may it not further be 

 inferred, with tolerable confidence, that the ova of the other and 

 more hardy species of the Salmonidee, were they similarly experi- 

 mented upon, would afford like results, confirmatory of those ob- 

 tained last year in some trials on the ova of the Salmon, and men- 

 tioned in my former letter to you? u A-jm jujjjl. jao io,yuii» ^yjjiit f 



The practical application of these 're^oilspidnd 6f f tiia»dortclU8^»fli 

 deducible from them, is obviousi!>jmdlneedmcBiratl)^^^iifuBe,dw:«ltii 

 upon. .V... ':,y\i\\ uri -iO(jr;)^i[= r ni ■r>n:,tiV'iYiJO^ 



]v.^iiaiT^ 1 am, my dear Sir, yours very truly, Mb "io 



ilLesketh How, Ambleside, - . JofiN DAtlYsdt no 



January 10, 1856. -ginuir^mo^ mum 9fio Biii iii :hii')h 



■' "Note on a new Class of Aloohil^." ^ ' By M^-^Aii^.^'ilMottrBbaadlf 

 A. W. Hofmann, Ph.D., F.R.S. &c. -ooioiii/ a>r^ 



On submitting to dry distillation glycerine, either alOne of toge* 

 ther with bisulphate of potassium or anhydrous phosphoric acid, 

 M. Redtenbacher obtained a remarkable product, to which he gave 

 the name of acroleine. Presenting all the characters of an aldehyde, 

 and approximating more particularly to vinic aldehyde by the general 

 aspect of its reactions, this substance changes under the influence of 

 oxidizing bodies, especially of oxide of silver, an acid being formed, 

 named by this philosopher acrylic acid, an acid which stands in the 

 same relation to acroleine as acetic acid does to aldehyde. ;;j 



The researches of MM. Will and Wertheim on the essential dils 

 of mustard and of garlic, tended to indicate a relation between these 



