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ON ANIMAL HEAT.

MRS. B.

It is because they usually live under ground, andseldom come into the atmosphere. They have im-perfect, and sometimes no discernible organs of re-spiration, they partake therefore of the soft oilynature of fish ; indeed, many of them are amphi-bious, as frogs, toads, and snakes, and very few ofthem find any difficulty in remaining a length oftime under water. Whilst, on the contrary, theinsect tribe, that are so strong in proportion totheir size, and alert in their motions, partake of thenature of birds, air being their peculiar element,and their organs of respiration being comparativelylarger than in other classes of animals.

I have now given you a short account of theprincipal animal functions. However interestingthe subject may appear to you, a fuller investiga-tion of it would, I fear, lead us too far from ourobject.

EMILY.

Yet I shall not quit it without much regret; forof all the branches of chemistry, it is certainly themost curious and most interesting.

CAROLINE.

But, Mrs. B. I must remind you that you pro-mised to srive us some account of the nature of milk.