Fixed Air on Vegetation.' 359 



was that your ftandard plants, had not been 

 placed in fimilar veffcls to thofe which had been 

 expofed to the fixed air; and the other, that, 

 as your experiments were made in Nooth's ma- 

 chine, and as you had not afcertained the pro- 

 portion of fixed air which was contained in your 

 vefiTel, it was, probably, much fmaller than you 

 had imagined. * 



To fhew the probability of this opinion, he 

 has related a number of experiments, by which 

 he found that fixed air, in all proportions, 

 from a ftate of purity, to that of a mixture of 

 \ fixed air to | common air, was injurious to 

 vegetation, and deftruflive to the colour of rofc 

 leaves Yet, with his ufual candour, he pub- 

 lifhed, in theAppendix to that volume, an account 

 of fcveral experiments, which I had tranfmitted 

 to him, in the latter end of the year 1776. f 



By thefe it appeared that a ftrawberry plant had 

 not only been preferved alive, expoffd in the 

 middle of Nooth's machine, to copious ftreams 

 of fixed air, from the 23d of April to the 14th of 

 May, but that the bloflbms, which were only 

 budded when put into the machine had actually 

 expanded. A ftrong proof that the plant had. 

 continued to vegetate. It was then alive, but 



* Dr. Prieftley was miftaken in this fuppofition, as 

 will appear in the fequel. 



t Thefe had been made previous to Dr. Prieftley'g 

 requcll. 



A a 4 rather 



