EXPERIMENT ON LARV^. 159 



of the muslin, or lace, do not interfere in the least 

 with the requisite change of air for respiration. 



Again, if after corking up the bottle for a short 

 time, we were to shake out all the caterpillars 

 from it, and then put into it a little water, in 

 which quick-lime has been slaked sold by chemists 

 under the name of lime-water, we should find 

 it become quite white and milk-like. This would 

 be, because, as the physiological chemist well 

 knows, the function of breathing causes carbonic 

 acid gas to be poured out of the body, no matter 

 whether it is the body of an insect or an elephant ; 

 and this gas has the property of turning lime-water 

 of the colour mentioned. Hence we have a second 

 and convincing proof that larvae breathe we 

 need scarcely remind the reader that caterpillars 

 are larvae and more than this, that the function 

 of breathing in them resembles, so far as the dis- 

 charge of this peculiar gas is concerned, the same 

 function, whether carried on in the human body or 

 in that of the most mighty and majestic of the 

 beasts of the field. 



The great chemist, Scheele, has experimented, 

 somewhat in the manner we have recommended, 

 upon the breathing of larvse. He found that when 



