PHENOMENA OF PLANT-LIFE. 57 



thermometer, in the shade, indicated 32 F. at two P. M. 

 A sugar maple was tapped 'at the ground, and fifty feet above 

 it, and while there was no flow from the lower orifice, the 

 upper one bled four drops per minute. 



On the twentieth of November last, the weather was cold, 

 and at eleven, A. M. there was a rapid fall of soft snow, fol- 

 lowed by a rising temperature. At half-past twelve, P. M., 

 the mercurial gauge, in the top of a sugar maple, indicated a 

 pressure of about nine feet of water, while u gauge at the 

 ground showed neither pressure nor suction. 



In the case of a tree tapped in 1873, on the north and south 

 sides, in order to compare the flow from each, it was found 

 that, for some reason, the north spout yielded nearly twice as 

 much sap as the south one, and flowed two weeks longer. It 

 appears probable that this was an exceptional instance, and 

 possibly to be accounted for by the fact, that the roots of the 

 south side ran under a highway, while those of the north side 

 luxuriated in a rich meadow. 



In 1874, another tree, about sixty feet in height and four 

 feet and ten inches in girth, was subjected to the same trial. 

 The total flow from the south side was eighty-six pounds and 

 four ounces, while that from the north side was sixty-eight 

 pounds and five ounces. Near the close of the season only, 

 did the flow from the latter exceed that from the former. 

 There can be no doubt that it is much wiser to tap all sugar 

 trees on the south side, because the sap will flow earlier and 

 more abundantly than from the shaded side, while the late 

 sap is of little value to the sugar-maker. 



Another sugar maple, seventy feet high and four feet in 

 circumference, was tapped on the south side in five places, 

 the holes being two feet apart on a vertical line, so that spout 

 number one was near the ground, number two, directly above 

 number one, number three, two feet above number two, and 

 so on. During the month of April, the sap from each spout 

 was weighed daily, and the results were as follows, viz. : 

 The total flow was one hundred and twenty pounds and one 

 ounce. From number one, near the ground, was collected 

 seventy-eight pounds and ten ounces ; from number two, 

 twelve pounds and two ounces ; from number three, five 

 pounds and ten ounces ; from number four, eight pounds and 



