GERMINATION OF SEEDS. 247 



good, and when the cause of their not growing is found 

 in the gardener or planter. To induce germination, 

 moisture, atmospheric air, and a certain temperature, are 

 indispensable ; and it is also requisite that light be ex- 

 cluded, until the nutriment in the seed is exhausted, or 

 until the root can draw nourishment from the soil. The 

 first effect of the air, heat, and moisture upon the seed is 

 to change its properties, — to convert its starch into sugar 

 — i. e. a sort of milky pulp, the proper food of the em- 

 bryo plant. If at this stage the seed becomes dry, its 

 vitality is believed to be destroyed ; but if these agents 

 are permitted to exert their influence, the contents of the 

 seed swell by degrees, and the first point of the future 

 root, having formed, breaks through the shell in a down- 

 ward direction, and at about the same time the point of 

 the future stem comes forth in an upward direction. The 

 presence of air, heat, and moisture is as indispensable to 

 the growth of the plant, as it is to the germination of the 

 seed. 



Now it often happens, when seeds are planted in fresh- 

 stirred ground, or where the soil is moist, they undergo 

 the incipient process of fermentation, and the earth not 

 being pressed upon them, and dry weather ensuing, the 

 moisture is abstracted, and the seeds perish. Too much 

 moisture is also often destructive to the vital principle of 

 seeds, — and others again are buried too deep to be vivi- 

 fied by solar and atmospheric influence. The first ob- 

 ject in planting, therefore, should be, to place the seed 

 just so far under the surface, and so to cover it with 

 earth, as shall barely secure to it a constant supply of 

 moisture. There are many seeds, as of the carrot, pars- 

 nip, orchard-grass, &c., which, if not previously steeped, 

 or the soil \\»ell pulverized and pressed upon them, fail to 

 grow for want of moisture. Hence, in sowing orchard- 

 grass, it is found prudent to spread the seed upon a floor, 

 and sprinkle it with water, before it is sown, and to pass 

 a roller over the ground after it is sown. And hence, in 

 nght garden mould, it is advisable to press, with the hoe 

 or spade, the earth upon all light seeds after they are 

 sown. 



