30 PEINCIPLES OF GARDENING. [CH. I. 



stagnant water, the seeds either decay without ger- 

 minating or germinate unhealthily. This arises 

 neither merely from its keeping them in an ungenial 

 temperature, nor only from the usual tendency of 

 excessive moisture to promote putrefaction ; but also 

 because the vegetable decomposing matters in a soil, 

 where water is superabimdant, give out carburetted- 

 hydrogen with acetic and gallic acids — compounds 

 unfavourable to the vegetation of most cultivated 

 plants, whilst the evolution of carbonic acid and 

 ammonia is prevented, which two bodies are bene- 

 ficial to the embryo plant. 



x\s water is essential to germination, and only a 

 certain quantity is required for its healthy progress, 

 so is it by no means a matter of indifference what 

 matters it holds in solution. Until germination has 

 commenced, no liquid but water at common tempera- 

 tures \sill pass through the integuments of a seed. 

 So soon as germination has commenced, this power 

 to exclude foreign fluids ceases, but the organs start- 

 ing into activity, the radicle and the plumule, are so 

 delicate, that the weakest saline solutions are too 

 acrid and offensive for them. So utterly incapable 

 are the infant roots of imbibing such solutions, that 

 at first they are absolutely dependent, themselves, 

 for their \ery existence, upon the seed-leaves ; and if 

 these be removed, the plant either makes no further 

 advance, or altogether perishes. Many years since I 



