[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 10º 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 10º a.m on 12th began to rise & rose steadily, by night & day till after 10º 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 24º than afterwards. Angle of filament when observation finished 8º a.m. Mar 15' was 60º 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 2º 30' than at any other period of equal length