202 THE NATURE-STUDY REVIEW [ 3 : 7 -oct., icp? 



seeds for instance, is almost never sown except during or after a 

 rain. A common practice is to cover beds in which seeds are 

 sown on the surface, or but slightly covered, with brush. The 

 brush shade the ground from the heat of the sun thereby keeping 

 the soil moist for the seeds. 



On the other hand, many seeds mould and are ruined by getting 

 too wet. Before planting seeds in the early spring, it is custom- 

 ary to wait for the sun to dry the excessive dampness out of the 

 ground; otherwise the seeds might decay before sprouting. 

 Plowing and spading greatly hasten the drying out of excessively 

 wet soil. Some land is naturally so wet that it has to be drained 

 by means of ditches and tiles before cultivated plants will grow 

 in it. Portions of some fields are so depressed that when a hard 

 rain follows planting water collects in the depressions and pre- 

 vent the seeds from sprouting. 



Seeds require heat of a certain degree in order to sprout quickly. 

 Prepare two chimneys of seeds alike in all particulars with the 

 exceptions that one is placed where it is warm while the other is 

 placed in the coldest place you can find. It is very easy to con- 

 fuse light and heat in this experiment. A dark corner may be the 

 warmest place in the schoolroom; in order to make no mistake, 

 place one of the chimneys out of doors in a shaded spot, or take 

 the temperature of different parts of the building and select a 

 spot that is decidedly cooler than the place chosen for the other 

 chimney. 



Light is unnecessary and even retards sprouting. Prepare two 

 chimneys of seeds, treat alike except about one chimney wrap 

 a number of thicknesses of dark colored paper gumming the 

 outer edge to hold it in place. When paste is dry you should be 

 able to slip the paper cylinder up and down in order to examine 

 the progress in sprouting made by the seeds. 



Applications of these lessons. The temperature of the soil is 

 quite as important a factor to consider in planting of seeds as the 

 presence of moisture. For this reason seeds are not placed in the 

 soil until the spring sun has warmed the earth considerably. 

 The turning up of the soil in the processes of plowing, spading 

 and harrowing very materially quicken the warming of the soil. 

 Seeds of cabbages, tomatoes, etc., are commonly started in the 

 house and cold frames that they may get more heat than is sup- 

 plied by the ground at that time of the year. Horse manure is 



