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the power of light. In houses the light usually declined before any 
sensible diminution of heat took place, and thus the leaves were caused 
to absorb a larger quantity of carbonic acid than the light had time to 
decompose. This excess being rejected at night had, in his 
opinion, led to the incorrect belief that plants respired carbonic acid, 
and the great heat at which Garreau’s only successful results were 
obtained were strongly in support of his view. 
The third statement, that plants respired nitrogen, was supported 
by no respectable evidence, and might be disregarded. It must be re- 
membered that the gaseous products of plants were likely to be con- 
siderably modified by the putrefaction of dead leaves and roots, the 
secretions of insects and exhalations from the soil, so that experiments 
required to be guarded by very stringent precautions. The odour of 
ammonia proceeding from the Chenopodium vulvaria was now per- 
fectly understood. The plant in question, an inhabitant of calcareous 
soils near the sea, had the peculiar property of assimilating carbonate 
of ammonia, the minute particles of which salt, on reaching the 
surface, readily decomposed liberating the gas. The phenomenon 
was a curious one, but had nothing to with the so-called vegetable 
respiration. 
He might refer to the statements lately advanced, on most 
insufficient evidence, that the lower forms of animals absorbed 
carbon and respired oxygen. Even were the phenomenon in question 
better established it would be necessary to remember that the boundary 
between the animal and vegetable kingdoms was by no means fixed, 
and that we had fair reason to doubt whether a being presenting such 
abnormal characteristics had been rightly classified. In the hopes 
that the Society might yet prodce a genius competent to unravel the 
great mystery connected with the gaseous products of the vegetable 
world, he had ventured to lay before it the brief statement of the 
known facts. 
After a cordial vote of thanks, proposed by the President (Mr. 
G. Scorr), “for a very lucid and admirable paper,” an interesting 
discussion followed, in which Messrs. HENNAH, PAYNE, W. H, SMITH, 
THE PRESIDENT, and Dr, HALLIFAX took part, 
