[46]

Apogeotropism

March 12-14' 15th 1878

Cytisus fragrans, a straight seedling vertical seedling, 12 inches in height was fastened down, so as to project about 10° degrees below horizon, filament fixed to extremity with bead & triangle of paper. & [sketch] rising traced on vertical glass; kept dark for first 3/4 of hour fell a little no doubt from weight & then began to rise by 10° a.m on 12th began to rise & rose steadily, by night & day till after 10° 30' P.m on the 13th — By next morning had fallen a little & had move a little to side of windows. This fall probably due to curtain in front removed for observation. Movement much more during first 24° than afterwards. Angle of filament when observation finished 8° a.m. Mar 15' was 60° above horizon. (See tracing). The most remarkable fact is extreme absence of any zig-zag straightness of line of dots (gives me much confidence in my observation for I cd hardly see dots till work completed) & unequal height to which stem moved after equal intervals of time. Sometime almost stood still. I infer, that as with light (proved by painting one side whole of the sides as well as under face, acted on by geotropism. (Tracing not greatly magnified) Rose far f more during the first 2° 30' than at any other period of equal length