[84]

Cabbage leaf (─*about 1 cm from the real tip)

Jan 25. 1879

Young plant growing in a pot in which it has grown in the g cold house for some time — The plant has 8 leaves; No 1 is quite small & undeveloped, No 3 is about 10cm long & has a glass filament with 2 triangles fixed to it, shellacced on to tip * of the leaf (The stem is firmly tied to a stick).

The plant was moved into House 3 to be observed & stands in the same relation to the light as it has done in the cold. Temperature in House 3 at 1. 5 pm is 11. C (Jan 25) —

Tracings on vertical part of big bell glass

Jan 25 it was observed at 11 am, 11 22, 12 20 pm, 1.5 1.50, 3.55, 6 40, 10 40; it moved down till 3.55 & by 6 40 had risen a good bit but by 10 40 it had sank again—

Jan 26 — I found the filament could reach the glass so that throws a doubt on the observations of Jan 25

Started again at 11 am, when it sank till 12. 55 and by 3. 20 when next looked at it had risen, & went on rising to 10 20 pm

Jan 27— 8. 25 am it had sunk since last night, & went on sinking till 4 35 2 50 pm, by 6 53 ; it was not looked at again till 4.35 when it was lower than at 2.50; by 6.53 it had risen a good deal & still more by 11.30.

(2

Jan 27. 79

Cabbage leaf

The angle of the midrib ie the straight basal part of the leaf & of the filament with the horizon were taken at 2.50 pm & 11.30 pm

at 2.50 midrib 65° above; filament 16

11 30 65° filament 27

That is the midrib did not rise perceptibly while the rip of the leaf rose 11°

Jan 28 — 9.15 am The leaf has sunk since last light; sunk still more by 12.30 & a little more by 4 pm when next looked at.

The following are the times of observation for the three days

[data not transcribed]

The tracing is multiplied about 4 times assuming that only the upper part of leaf moves [Figure]

[85v]

[calculation not transcribed]