40 



HAREINGTON ON THE SAP 



is now (May, 1887) thirty-five feet five inches high, and two feet three inches in circum- 

 ference, one foot above the ground ; while the female tree is thirty feet four inches high, 

 and two feet two and a half inches in circumference, one foot above the ground. They 

 were both tapped in the first week of April, by boring a half inch hole to a depth of about 

 an inch and a half and inserting a piece of glass tubing. The sap, which was collected in 

 glass bottles, did not begin to run until April 6th and 7th, respectively, in the case of the 

 female and male trees. After the 20th of the month the flow ceased entirely. On looking 

 at the accompanying tables it will be seen that the male tree yielded more sap than 

 the female, but that the latter contained on the whole a larger proportion of sugar. In 

 Table I are given not only the daily quantities of sap collected, but the maximum and 

 minimum temperatures for each day, the range of temperature, and the direction and 

 velocity of the wind. It will be observed that the daily minimum temperature (attained 



Table I. ' 



as a rule in the night), during the period in question, was always below the freezing point, 

 except in one instance (the night of April 9th), and then the flow of sap was suddenly 

 checked, so that while on the 9th, 1,400 c.c. were obtained, the total quantity on the 10th 

 was only 85 c.c. The 10th was the warmest day during the period, and also the day on 

 which the wind was highest. After the 20th, there were no more frosty nights and the 



' The meteorological data are from the records of McGill Observatory kept by Prof. McLeod. 



