inner hole, and an old fashioned sheet iron spout driven under 

 the outer one, so that the sap from the inner and outer wood 

 could be gathered separately. 



At the time of tapping, the rate was : Inner hole, 9 c.c. per 

 minute ; outer hole, 6 c.c. per minute. 



Three days later, April 20th, the run was 11 c.c. and 3 c.c. 

 respectively. Thinking that the greatly decreased flow from the 

 outer hole might be due to the free exposure of the sap-wood to 

 the air, another similar tree was tapped in the same manner. 

 The rate of flow from this second tree was 16 c.c. from the 

 inner, and 13 c.c. from the outer hole. In both trees the flow 

 from the inner wood exceeded that from the outer wood, al- 

 though the diameter of the outer hole was double that of the 

 inner one. 



In 1894 four trees were tapped as follows : R tapped 2^ 

 inches deep with a |f inch bit, and the hole continued 2^ inches 

 with a Y^ inch bit. An iron spout was driven into the inner 

 hole, and the outer hole was closed with a rubber stopper 

 through which tubes were passed to give outlet to the sap from 

 the outer and inner wood without subjecting the outer wood to 

 exposure to the air: ,5 tapped 5^ inches deep with a ^ inch 

 bit. A thin rubber stopper, through which a small tube was 

 passed, was driven to the centre of the hole, the tube extending 

 out through the centre of the spout driven into the outer wood 

 of the tree. We were thus able to compare the rate of flow from 

 the outer and inner wood with the same bore throughout : T 

 tapped twice with a 2/^ inch bit. The holes 4 inches apart and 

 apparently in equally favorable positions, one hole 6 inches 

 deep, the other 2 inches deep : U standing near and similar to 

 T, tapped with a ]{{, inch bit, 6 inches deep. Table 3 gives the 

 rate per minute in cubic centimeters. 



