480 Dr. R. A. Smith's Remarks on 



This condensed moisture is not easily obtained in sufficient 

 quantities ; but on the occasion of a concert at the Mechanics' 

 Institution here, I collected 200 grs. from one window, letting 

 it drop into a small platinum basin. By burning 5 grs. of this 

 the smell was made apparent; by burning 150 grs. a strong 

 smell of human sweat came otF, continuing until the sub- 

 stance was dry. It will therefore be difficult to tell how 

 much organic matter was contained in the whole, as a great 

 deal evaporated, but above 2 grs. were left. When heated, 

 this smelt like burning flesh, and was very disagreeable. 



We know that volatile products escape from the bodies of 

 animals, and are mixed with the air so as to undergo com- 

 plete oxidation ; but this cannot be any important part which 

 the air has to perform, as the following facts show that the 

 oxidation is best effected in the earth. It may however be 

 important that bodies should decompose in this manner, be- 

 cause they are also more readily conveyed by the atmosphere 

 to plants. 



When we see the volatile and decomposing matter from 

 the body so distinctly as in the last case mentioned, it is 

 possible for us to conceive that infectious matter is not a sub- 

 stance so very subtle as has been supposed ; we have only to 

 allow it to be in a peculiar state of decomposition. 



Burning in a platinum crucible and the odour discover a 

 very small quantity of organic matter, such as it is scarcely 

 safe to trust to the results of the balance. I hope in a future 

 paper to show the qualities of several water districts in this 

 respect, but at present give an abstract only of the results of 

 such observations as I have made, hoping that the constant 

 and almost monthly variation of the w ater of whole districts 

 will be a sufficient excuse for the absence of an arranged set 

 of results. 



When water from a peaty district is boiled down and the 

 ashes burnt, the smell of peat is distinctly observed. The 

 river Dee at Chester contains 25 grs. of organic matter to the 

 gallon, and the smell is as perceptible as at Llangollen, close 

 to a peaty district. 500 grs. of the water are sufficient to 

 indicate this very strongly. Water from the Lancashire and 

 Yorkshire hills may be known to contain peat also by testing 

 the same quantity, although many of the streams do not con- 

 tain 15 grs. per gallon. Some of the canals near Manchester 

 may be known to be supplied from peaty districts by the 

 same tests. But whenever we approach a town the smell 

 from the burnt ash changes, and organic matter from the de- 

 composition of pi'otein compounds is distinctly traced. So 

 easily is this known, that Mhen water was brought to me 



