& As thus the nitrogenous portion of the air seems 

 neither to produce nor to suffer any change in the 

 process of germination, let us next inquire into the 

 changes which the oxygenous part, the other ele- 

 mentary portion of our atmosphere, undergoes. Mr 

 Scheele and Mr Achard proved that oxygen gas 

 was absolutely necessary for the germination of aH 

 seeds. Mr Gough likewise observed, that steeped 

 barley-seeds, supported by means of a small hoop 

 in an inverted jar of atmospheric air, germinated 

 freely : the residual air, on the fifth day, being 

 passed through lime-water, precipitated the lime, 

 and, when thus freed from carbonic acid, was found 

 to have lost nearly one-sixth of its original bulk, and 

 the remaining air repeatedly extinguished a taper *. 

 Some grains of barley, which had been soaked in 

 water twenty-four hours, were introduced by Mr 

 Cruickshank, on the 1st of December, into a jar of 

 common air inverted over water, and preserved in a 

 temperature between 60 and 70. At the end of 

 five days they began to grow, and on the 28th day, 

 the greatest part of them had thrown out shoots half 

 an inch in length. Germination continued to pro- 

 ceed on the 7th of February, when the barley being 

 withdrawn, was found to be very sweet, and nearly 

 converted into the state of malt. The air in the jar 

 was found to consist only of nitrogen and carbonic 

 acid gases, the whole of the oxygen having entirely 

 disappeared. When the experiment was made in a 

 jar containing forty -six measures of very pure oxy- 

 gen gas inverted over mercury, the process of ger- 



Manchester Memoirs, vol. iv. p. 319, 



