30 FARM AND SCHOOL PROBLEMS. 



^ 



tile) 100 feet apart and require 436 tile per acre, what was the total cost 

 of the laterals for a complete drainage of the 40 acres @ 1.5 per tile 

 plus 28c per rod for putting in the tile at a depth of 2 feet and 10 inches? 



4. What was the total cost of putting in the complete system in 

 the 40 acres mentioned in the three foregoing problems? 



5. If a 40 acre field which is thoroughly drained yields 70 bushels 

 of corn per acre, which is 50 per cent more than the yield before it was 

 drained, how many such crops will be required to pay for the cost of 

 tiling as given in the solution of problem 4, if the corn is sold at the 

 present market price? 



Experiments. 



CAPILLARITY AND OSMOSIS. 



1. Fill two glass jars of equal size with water. In one of these 

 submerge the roots of a healthy growing plant. Note carefully the differ- 

 ence in the amount of water evaporated from each jar in a given time. 



2. Equipment. 



(a). Soils of different kinds, sand, clay, gravel, etc. 

 (b). Cans or jars of equal size and weight. 



Directions. Fill each can or jar to the same depth with a different 

 type of soil. Pour equal quantities of water into each. Mix thoroughly. 

 Weigh each day and note the amount of water evaporated from each 

 and tabulate the results for one week. What is the per cent of moisture 

 lost from each kind of soil at the end of the experiment? 



3. Show by means of glass tubes of different diameters, how the 

 water in the tube of least diameter will rise to the greatest height. 



4. Cut slices from a pared potato and place some in pure water 

 and some in salt solution. In the course of about an hour, examine and 

 compare results. 



5. Get a thistle tube or lamp chimney and cover the end with parch- 

 ment or piece of bladder. Fill with a strong solution of salt. See that 

 the tube or chimney will hold the liquid when poured into it. Fasten the 

 tube into a jar partly filled with water, so that the water in the jar is 

 just level with the salt solution in the tube. After an hour observe the 

 rise of water in the tube above the level of the water in the jar. The 

 process by which the water enters the tube is called osmosis. 



6. Place a young green plant with its root system in a jar. Pour 

 into the jar enough water to cover the roots. Cover the top of the jar 

 around the stem so as to prevent evaporation of water. Weigh carefully 

 at certain intervals and find loss of weight by water passing upward 

 through the plant. What is this movement called? f 



7. Fill a two-inch gas pipe with water. Stopper each end to pre- 

 vent water from running out. Place the pipe in a horizontal position, so 

 it will be as nearly level as possible. Remove the stopper at one end. 



