58 PHENOMENA OF PLANT-LIFE. 



seven ounces ; and from number five, fifteen pounds and four 

 ounces. These facts are, in the main, what would be 

 expected from the other observations made concerning the 

 flow of maple sap. 



The effect of increasing the number of spouts inserted into 

 a tree was tried on two red maples, which flow much less than 

 the sugar maple and for a shorter time. Ten spouts in one 

 tree, sixty feet high and four feet eight inches in girth, were 

 found to flow, during the first half of April, seventy-eight 

 pounds and eight ounces, while one spout in a similar tree 

 flowed less than half as much, or thirty-five pounds and two 

 ounces. There can be no doubt that the quantity of sap 

 obtained from a tree by the use of many spouts is greater 

 than that from a limited number, but it is not likely to contain 

 so large a per cent, of sugar. Still, if it be true, as seems 

 probable, that the withdrawal of sap exerts no deleterious 

 influence upon the health and vigor of a tree, and the sap is 

 richest early in the season, it would seem best to insert more 

 spouts, and so extract the sugar in its purest condition as 

 rapidly as possible* This, of course, would necessitate a 

 greater expenditure for buckets, which might possibly coun- 

 terbalance the advantages of the new method. Experiments 

 might be easily instituted to determine the facts in regard to 

 this matter by any intelligent sugar-maker. 



In regard to the origin of cane sugar in the sap of the 

 maples, the butternut and the black walnut, we must, for the 

 present, admit that we have not yet discovered it ; though 

 the singular fact that the species which yield this sugar belong 

 to that class of trees which only flow freely after severe frost 

 seems to indicate that freezing and thawing may have some 

 influence upon its production. 



It will be seen, from an examination of the table relating 

 to the composition of saps, that the sap of the wild grape is 

 almost pure water, and that it contained, on the fifteenth of 

 May last, no trace of either cane sugar, glucose or starch. 

 There is, however, in the wood of the roots and stems of the 

 genus Vitiss. great quantity of a colorless, translucent, almost 

 tasteless mucilage, which is abundantly exuded from the pores 

 of a coss section made at any time when the roots are dor- 

 mant. Very little even of this seems to escape from a bleed- 



