106 ROOTS 



various chemical salts dissolved in water. These are the 

 best for experimental purposes. A good nutrient solution 

 may be made by using the following formula : 



Calcium nitrate 6 g. 



Saltpeter l|g. 



Epsom salt l|g. 



Neutral potassium phosphate . . . 1^ g. 



Common salt l^g. 



Dissolve the above in 600 cc. of distilled water and keep 

 it in a corked bottle in the dark. 



When it is desired for use, shake it thoroughly and dilute 

 10 parts to 48 parts of distilled water. 



To prove the value of the solution try it on seedlings, 

 cuttings, and potted plants. Prepare three tumblers as 

 follows: (a) full of distilled water, (6) full of well water or 

 hydrant water, and (c) full of distilled water, into which the 

 nutrient solution has been added according to direction 

 (10 parts to 48 of water). 



^,ow carefully place some seedlings which have been 

 sprouted on blotting paper or cloth upon a cork float and 

 fasten them with a bit of cotton batting so that their roots 

 can be wet with the contents of the tumblers. Arrange 

 three sets of seedlings, one in each glass. 



After a week which seedlings are growing best ? Why ? 



Repeat the preceding exercise, using cuttings of willow, 

 poplar, or tradescantia which have been previously rooted in 

 water. 



Water two potted plants of about equal size at the same 

 time every day, giving to one only distilled water and to the 

 other equal portions of a nutrient solution. 



How do they compare in size, number of leaves, etc., at 



