Image from page 129 of "Some apostles of physiology : being an account of their lives and labours, labours that have contributed to the advancement of the healing art as well as to the prevention of disease" (1902)
Title: Some apostles of physiology : being an account of their lives and labours, labours that have contributed to the advancement of the healing art as well as to the prevention of disease
Year: 1902 (1900s)
Authors: Stirling, William, 1851-1932
Subjects: Physiology Physiologists Physiology
Publisher: London : Priv. print. by Waterlow and sons limited
Contributing Library: West Virginia University Libraries
Digitizing Sponsor: LYRASIS Members and Sloan Foundation
Click here to view book online to see this illustration in context in a browseable online version of this book.
Text Appearing Before Image:
feet 9 inches ; from o to u,32 feet 9 inches. The branches to which a and o were fixed were thriving shoots twoyears old, but the branch ob was much older. When I first fixed them, the mercury was pushed by the force of the sap, in all thegages down the legs 4, 5, I 3, so as to rise nine inches higher in the other legs. The next morning at 7 a.m. the mercury in a was pushed 14 + ^ inches high, in b12+ |, in c 13 + h. The greatest height to which they pushed the sap severally was, a21 inches, b 26 inches, c 26 inches. The mercury constantly subsided by the retreat ofthe sap about 9 or 10 in the morning, when the sun grew hot; but in a very moist foggymorning the sap was later before it retreated, viz., till noon, or some time after the fogwas srone. ( 76 ) About 4 or 5 oclock in the afternoon ; when the sun went off the vine, the sapbegan to push afresh into the gages, so as to make the mercury rise in the open legs; butit always rose fastest from sun-rise till 9 or 10 in the morning.
Text Appearing After Image:
HALES S METHOD OF MEASURING THE FORCE OF THE ASCENT OF THE SAP IV THE VINE. The sap in A (the oldest stem) played the most freely to and fro, and was thereforesoonest affected with the changes from hot to cool, or from wet to dry, and viceversa. And April 20, towards the end of the bleeding season, b began first to suckup the mercury from G to 5, so as to be 4 inches higher in that leg than the other. ButApril 24, after a nights rain, b pushed the mercury 4 inches up the other leg, a did notbegin to suck till April 29, viz., 9 days after b ; c did not begin to suck till May 3, viz.,13 days after 6, and 4 days after a. May 5th at 7 a.m. a pushed 1 inch, c 1 + .„ buttowards noon they all three sucked. I have frequently observed the same differencein other vines, where the like gages have been fixed at the same time, to old and youngbranches of the same vine, viz., the oldest began first to suck. In this experiment we see the great force of the sap, at 44 feet 3 inches distancefrom the
Note About Images
Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original work.