500 P«ILOSOPHICAL TRANSACTIONS. [aNNO I67I. 



These trees ran above two quarts in the morning. The weather glass con- 

 tinues the same, viz. about 1 1 inches water, these two clays. Thursday the 

 14th it was Qi only. Friday the 15th, my weather glass at noon was advanced 

 from 9 to 10^, yet the quantity of birch water this day exceeded my former 

 from these trees, for I had above 2-^ quarts before noon. 



But for cold, I find that the air, when any whifling blast of cold wind stirs, 

 stays my birches. I want a wind-fane. 



Saturday the l6th, these 24 birches began to run presently after sun-rise, 

 and ran about three quarts, and ceased about two o'clock in the afternoon, 

 having till then continued to run. Sunday the l7th, it rained so that we 

 could make no observations what sap these trees might spend; neither did rain 

 and all amount to much above a gallon and a half. Monday the 18th they 

 ran until noon. Tuesday and Wednesday the 19th and 20th, wherein was 

 expected greater store of sap, after the rain, the trees spent not a drop. Sa- 

 turday the 23d, my weather glass stood at 7-k; it being a rainy and boisterous 

 morning, the rain not allaying the wind. At 9 o'clock of that forenoon, my 

 birch water worked in the barrel per se : Which seems to verify Mr. Souton's 

 relation from his brother, a Swedish merchant, importing that birch water in 

 Sweden works alone ; perhaps collected in great quantity. Only I put a very 

 few cloves into my sap. Boiled to a third or less, it keeps well, especially 

 when boiled with the buds or sprigs of the same tree, as I have been in- 

 formed. 



April 16, 17, 18, in the year 1670, birch sap mixed with rain water at the 

 tree, fermented with rosemary sprigs steeped in spirit of wine : which warmed 

 the stomach as strong wine, and pleased the palate ; though the taste in the 

 mouth was somewhat waterish. 



A Letter by Dr. Tonge, about the retarding the Ascent of Sap ; 

 with some other Queries relating to that Subject. iV^GS, p. 20J2. 



Last night Sir Robert Moray did me the favour to acquaint me in discourse 

 with some particulars about the gathering of sap in fruit trees, and the retard- 

 ing the ascent thereof; which he had received from an eminent planter in 

 Glocestershire : concerning which, I thought it fit to communicate some re- 

 flections of mine. 



It was proposed to me by way of quere; How to gather every drop of sap 

 that should rise in any fruit tree ? This, I said, I thought not feasible, by 

 what I had hitherto experienced, though deserving of farther inquiry here- 

 after. 



