28 Principles of Plant Culture. 
36. Germination may be Hastened by Soaking Seeds 
before planting. Since seeds cannot germinate until 
nearly or quite saturated with water (29), and since they 
absorb water faster from a very wet than from a damp me- 
dium (27a), and in a warm than in a cool temperature (27c), 
when the soil to receive the seeds is only slightly moist, we 
may hasten germination a little by soaking the seeds, before 
planting, in warm or slightly hot water until they have 
swollen. The heated water not only penetrates the seed 
faster than cold water, but the heat appears to-stimulate the 
protoplasm (13), so that increased vigor is imparted to the 
seedlings. This method is sometimes practiced hy garden- 
ers with sweet corn and some other seeds, and its use might 
possibly be extended with profit. The water should not be 
heated to more than 110° to 120° F. and the soaking should 
be continued only until the seeds have fully swollen. 
Soaking is more important with seeds having seed-cases 
that do not readily transmit water at growing temperatures, 
as of the honey locust, canna, thorn apple. etc., (27d). Such 
seeds, particularly if they have been allowed to become dry, 
are generally soaked before planting in hot water until 
swollen, otherwise they might lie in the ground for months 
and even years before germinating. In treating such seeds 
to hot water, unless the temperature at which they swell is 
known, the water should be heated very gradually uutil the 
seeds begin to swell, when it should be maintained at that tem- 
perature until they are fully swollen. It is of interest that 
seeds of the honey locust may be immersed for a time in 
boiling water without destroying their vitality, but such 
treatment is not to be recommended for any seeds. In seeds 
of this class, 
