Page:Scientific Memoirs, Vol. 1 (1837).djvu/35

Rh oil of colza, and after having waited until the needle recovered its original position we reestablished the calorific communication.

The deviations obtained through the different thicknesses of the liquid are exhibited in the following table.

The free radiation being always represented by 1000, the respective quantities of the rays transmitted and those stopped are found to be:

If we suppose the last layer (of 108mm·274) subdivided into six parallel slices of the following degrees of thickness: 6mm·767, 6·767, 13·535, 27·069, 27·069, and 27·069, we shall be able to determine, by means of the numbers contained in the two last columns, the quantity of heat incident to the first surface of each of these slices and the quantity lost in the passage. Dividing the second by the first we shall ascertain the loss. It is unnecessary to exhibit the operations in detail, as they are in all respects similar to those which have been performed in reference to the screens of glass. Here are the final results: