8 



initiation was considerably hastened : the column of 

 gas on the 10th day had suffered no apparent 

 change ; and the residual air then consisted of car- 

 bonic acid, mixed with only l-50th of its bulk of 

 oxygen. The barley was partly converted into malt * . 

 These experiments teach us, that oxygen gas is es- 

 sential to the process of germination ; that it gra- 

 dually and completely disappears during the conti- 

 nuance of that process ; and that a large quantity of 

 carbonic acid supplies its place. 



7. M. de Saussure junior, instituted some experi- 

 ments to determine the proportion which the car- 

 bonic acid, produced in germination, bore to that of 

 the oxygen gas, which disappeared in that process. 

 He conveyed eighteen peas into a glass-vessel, the 

 mouth of which was plunged in mercury, and which 

 contained 11.5 cubic inches of atmospheric air, that 

 had been previously well washed in lime-water. 

 About one-fourth of a cubic inch of water was then 

 passed into the jar, and floated on the mercury, so 

 that the peas were about half immersed in it. In 

 ten days the radicles had sprouted about one-third 

 of an inch ; and the air in the jar, after making the 

 necessary corrections for pressure and temperature, 

 had undergone no sensible diminution of volume. 

 The residual air being submitted to analysis, lost 

 i|o by agitation with lime-water, and the remain- 

 der afterwards suffered a further loss of - by the 

 eudiometrical test of phosphorus. If the air he em- 

 ployed be held to contain ~ of oxygen gas, (which 



Experiments on Sugar, p. 213. 215. 



