466 THE ZOOLOGIST. 
I have never actually seen, or even heard of, a skeleton really made 
in this way, though ants, doubtless, especially in hot countries, will 
make short work of the flesh of an animal’s body, leaving at least 
all the larger bones untouched. But we must adopt some safer 
and more universally applicable method of proceeding. Another 
common idea is that some “chemical” substance is necessary to 
steep them in for dissolving the soft parts, and I am often asked, 
“ What acid do you use for this purpose?” when a little reflection 
would have shown that the bones would be the first parts to dis- 
appear under the influence of such a menstruum. No, water—pure 
water—is the only thing required in preparing bones and skeletons 
in the great majority of cases, and in the proper use of the water 
the art of “ macerating,” as it is called, chiefly consists. 
This process is nothing more or less than placing bones in 
water and leaving them undisturbed until putrefaction of all 
the flesh and blood remaining on and around them and within 
the hollows and small cavities of their interior, takes place, and 
these soft parts entirely lose their form and structure and become 
converted into liquids and gases mingled with the water or 
escaped from its surface; so that when the bones are removed 
and well washed, nothing remains but the comparatively inde- 
structible true osseous tissue, which, when dried, is hard, clean, 
and without smell. 
Maceration consists, then, essentially in the destruction of the 
soft tissues by putrefaction, and certain circumstances are essential 
or favourable to the success of the process. In the first place, the 
water should not be too abundant in proportion to the amount of 
animal matter to be destroyed. Then it should never be changed 
or disturbed until the process is completed. The surface should be 
exposed to the air, and the loss from evaporation supplied from time 
to time. The temperature should be uniform and elevated. Cold 
checks the process; freezing arrests it altogether. If the heat is 
too great the bones are often greasy and discoloured, as when they 
are prepared by boiling. It is to the fact that the process varies in 
rapidity according to so many circumstances that the chief practical 
difficulty, which is to know when it is completed, is due. If the 
bones are taken out too soon, unless they are returned immediately 
to the same water, a check takes place in their preparation. To 
estimate the necessary time is a matter acquired only by practice 
and knowledge of the surrounding circumstances. Much will 
