394 PRACTICAL ANATOMY. 



is apt to crack by bending the preparation. The cracks appear white 

 and mealy, as if the gum had lost its cement by drying. If a little 

 more tenacity could be given to it so as to avoid its cracking and not 

 prevent its drying, it would be preferable to the copal varnish commonly 

 used. 



Of the Preparation of Bones. — After roughly removing the flesh, &c, 

 the quickest way, without boiling, to clean them, is to put the bones 

 into a tub, with a loose cover, so as to let the flies get to them ; they 

 will fly-blow them immediately, and in a fortnight's time they will have 

 entirely destroyed the flesh. However, this can only be done in 

 summer. 



Bones that have been steeped in water, either after boiling or not, 

 are generally either of a black greyish colour, if they have been steeped 

 long enough, or they are of a pretty good white : these colours arise 

 from an entire want of grease, and these colours are always brightest 

 in the middle of the bone where there is the least grease. These are 

 the most promising colours, for the white will remain and the grey or 

 black will become white by being exposed to the air ; but what is most 

 valuable is the want of grease. 



If bones are of a dark or dirty brown when taken out, we may be 

 pretty sure that they have not a great deal of osseous matter ; and are 

 therefore light and bad bones. This colour is often attended with 

 grease, but whether it is or not, it is a bad one ; they never become 

 white of themselves, and it is hardly possible to make them sa by art ; 

 for they seem to be dyed, and that a little way into the bone ; but it is 

 always of a deeper colour near the surface than in the substance of the 

 bone. 



If they are taken out of a pretty bright or whitish yellow, or a little 

 on the orange colour, we may be sure they will be greasy, especially if 

 they feel slippery or saponaceous. This colour will be most at the ends 

 of bones, and it often seems mixed with the dark brown, and is gene- 

 rally attended with a yellow transparency. 



When this is the case, they have not lain long enough in water ; and, 

 indeed, there is a great chance against their ever becoming free of 

 grease before the bones are spoiled by steeping, if they have lain so 

 long already as to have destroyed the flesh. This colour, in general, 

 attends a good bone, or in other words, a strong one. 



The human flesh is longer in rotting than in any other animal; espe- 

 cially the tendons, ligaments, and cartilages ; it becomes more hard by 

 steeping, but in other animals it seems to dissolve. This is most so in 

 old people. 



Separation of Cuticle. — Putrefaction and boiling water separate the 



