GERMINATION OF SEEDS? 221 



£00 grains of barky, lost 8*00 grains 



120 grains lost 6'40 



100 grains lost 5"6'0 



40 grains lo^t 2'30 



30 grains lost 2 ,c 20 



30 grains lost 2' 10 



I merely give these results as means of preventing unne* 

 cessary trouble and waste of time in others, and not as of 

 any other importance. The seeds were continued in the 

 air, until the increase was considerable, and the oxigeu gas 

 was for the most part exhausted, as appeared by the ac- 

 customed tests of limewater, and impregnated sulphate of 

 iron. 



In proceeding to detail the following experiments, which Experiments 

 appear to me decisive of the absorption of oxigeu gas, 1 am uJjJJ^JLg, f 

 compelled to observe, I have found it impossible to vary oxigtn gas. 

 and continue some of them to the extent I intended, hav- 

 ing been often interrupted by the sudden intense coldness 

 of the weather, occasional illness, and the indispensable 

 concerns of business. In most of them, where it was at all 

 necessary, the usual corrections, according to the calcula- 

 tions of Gay Lussac, for change of temperature and pres- 

 sure were made, and for this purpose the barometer and 

 thermometer at the beginning of every experiment and ana- 

 lysis were duly noted. 



Sincerely wishing the little experience I may have ac- 

 quired in this sort of manipulation should be serviceable to 

 Others just entering upon the same laudable pursuits, I 

 take the liberty here of strongly recommending the eudio- 

 metrical apparatus of Mr. Pepys, as the easiest and most Mr p e , 

 correct that can be used for the analysis of gasses. When diometer. 

 accurately made, and the precautions and directions adopted 

 as stated in your Journal, vol. XlX, p. 86, scarcely any 

 obstacle intervenes to prevent its being managed with faci- 

 lity. Great attention should however be paid, when tilling Precautions, 

 the elastic gum bottle with the eudiometric liquor, to the 

 expelling from it every bubble of air; which 1 have tound 

 can be effectually done no other way, than by frequently 

 pressing the bottle in a vertical position, keeping the end 



of 



