292 REVIEWS, 



study or depth of philosophy to lay down the precise limits 

 of each branch of science ; and to most Germans and Eng- 

 lishmen it will seem strange that a man of Lacaze Duthiers' 

 merit should trouble himself as to the title given to such 

 researches as that on the otocysts of molluscs, published in 

 this journal. 



" Let liim name it who can, it,s beauty is still the same." 



Still, if a barren controversy about words can be avoided, it 

 may be well to consider how far zoology can be reckoned, 

 with chemistry and physiology, an experimental science. 



In M. Bernard's ' Report on the Progress of Physiology in 

 France ' (1867) , he says: — " L'observation considere les pheno- 

 menes dans les conditions ou la nature les lui offre. L'experi- 

 menteur les fait apparaitre dans les conditions dont il est 

 maitre ;" and, again :^ ''Nous ne pouvons que regarder les phe- 

 nomenes dus a l'observation tandis, que nous pouvons faire 

 apparaitre ou disparaitre ceux de I'experience suivant notre 

 volonte." 



The broad distinction between observation and experiment, 

 as methods of acquiring knowledge, has been common pro- 

 perty since the time of Bacon ; but it is only a broad distinc- 

 tion, and no hard line can be drawn between the two. Thus, 

 descriptive anatomy, which has always been considered the 

 type of a science of observation, is far from being a mere pas- 

 sive contemplation of objects. A well-dissected limb is in 

 anything but a natural condition. Every process of injection, 

 preservation, and dissection is a step away from the purely 

 " contemplative " view of the phenomenon ; and when minute 

 anatomical structure is investigated, the process becomes 

 still more complicated. A section of skin, with the vessels 

 injected with blue solution, hardened in chromic acid, em- 

 bedded in gum, its nerves stained with gold, its epithelium 

 with nitrate of silver, and its nuclei with carmine, is this 

 " une phenomene dans les conditions ou la nature la lui 

 offre " ? Why is not trying what will be the " behaviour " 

 of a leucocyte with magenta as much an experiment as feed- 

 ing a vorticella with carmine ? and why is not either pro- 

 cess as much an experiment, according to M. Bernard's 

 definition, as regulating the supply of food sent through the 

 arteries to the elements of a rabbit's ear by dividing its sym- 

 pathetic nerve ? 



The fact is, that mere passive " contemplation of pheno- 

 mena in the conditions which nature offers " is not science 

 at all ; it is the business of the artist, not of the philosopher. 

 ' ' Revue des Cours Scientifiques,' 1869. 



