Messrs. Gladstone on the Growth of Plants in various Gases. 215 



down in a perpendicular breast of about a yard in height, driving 

 the fresh water before it. This point is about 9^ miles from 

 Chipping, following all the windings of the streams, and about 

 220 feet lower; and as I find that the flood reached it at about 

 Qh 30m Y.M., it would seem that it took 2^ 30"^ or thereabouts 

 to travel that distance, which corresponds to the rate of 3*7 miles 

 an hour. For several days afterwards the water continued 

 muddy, and a thick deposit is left all along the banks of the 

 Hodder and Kibble. 



It is worth remarking, that on the south-east side of the valley 

 bounded byLongridge Fell there was no rain; and in several places 

 at the bottom of the valley, within two miles of Leagram, I found 

 on inquiry that there had been nothing but a few drops. Every- 

 where I was told that the lightning was terrific. At Stonyhurst 

 there was no rain, but the lightning was very brilliant, and the 

 thunder almost incessant. The storm appeared to be raging in 

 the direction of Chipping. Still about two miles to the east, at 

 Higher Hodder Bridge, the rain fell with great violence for 

 about fifteen minutes. From a point in this neighbourhood, the 

 whole range of Bowland Hills appeared enveloped in a dense 

 black cloud, from some points of which the rain seemed to be 

 descending in torrents. This feature, and the lurid aspect of 

 the sky, joined to the frequent displays of lightning of the most 

 vivid description, rendered the whole scene one of the most im- 

 posing I remember to have witnessed. 



XXXII. On the Growth of Plants in various Gases. 

 By Dr. J. H. Gladstone and G. Gladstone, Esq."^ 



THAT both plants and animals are very dependent upon the 

 chemical composition of the atmosphere in which they live, 

 and that the constituents of it play important functions in their 

 oeconomy, are matters of every-day observation. These consti- 

 tuents are oxygen, nitrogen, aqueous vapour, a small amount of 

 carbonic acid, a still smaller quantity of ammonia, and occasional 

 traces of other gases. 



Since the plant stores up oxygen within its cells at certain 

 periods, it can scarcely be doubted that this gas fulfils some im- 

 portant office ; but, excepting in the case of the germination of 

 seeds, we have little information upon this subject. 



It has been doubted whether any of those vegetable principles 

 which contain nitrogen derive that element by direct assimilation 

 of the gas existing in the atmosphere. Ammonia is looked upon 



* Communicated by the Authors, being the substance of two papers read 

 before the British Association at the meetings of 1850 and 1861. 



Q2 



