128 Messrs Edwards and Colin upon the 



germination ; still less with the supposition that this disengage- 

 ment proceeded from air contained in the beans ; which 

 idea soon became wholly improbable from the unceasing con- 

 tinuance of the disengagement of the gas, and to such an ex- 

 tent that it could not by possibility be attributed to this cause. 



First of all, it is certain that the gas came from the beans 

 themselves, for before we introduced them into the apparatus, we 

 were careful to put them in water and shake them well, thereby 

 detaching all the air which was attached to their surface. 

 For a long time after they were plunged into the water of 

 the bottle, no gas was seen to issue from theu' sm-face, and 

 it made its appearance only by degrees. Besides, on other 

 occasions when the beans were cut through, we have seen it 

 proceed from the parenchymatous substance itself. Many of 

 the beans were actually made to float by the air-bubbles which 

 adhered to them, and fell to the bottom so soon as the bubbles 

 burst. 



After a period, which was never less than four days, we put 

 an end to the experiment. Our first care was to weigh the 

 beans, that we might thereby determine the quantity of water 

 which they had absorbed, and we invariably found that it ex- 

 ceeded their own weight. In reality, the mean weight of the 

 beans employed was 1540 grains (avoirdupois), and the mois- 

 ture which swelled them amounted to about 1848 grains. 



The most essential point of all in this investigation was to 

 certify that the beans were alive, and in a state of germina- 

 tion ; for it is evident that it is a condition which must indis- 

 pensably be established, that the disengagement of the gas 

 which is effected in the water is the result of a natural and 

 normal function. 



When taken out of the liquid, some of the beans had a 

 chink opposite to the point M'here the radical is situate ; but 

 there were only three or four in this condition. 



If the beans were living, the function was normal : so we 

 planted them, that we might have an opportunity of compar- 

 ing them with the same number of other beans which had not 

 been subjected to any experiment, and we had the pleasure 

 to see them spi'ing up quite as well as these. The best me- 

 thod, however, of conducting the experiment is to keep them 



