1878.] On the Transpiration of Plants. 165 
were taken up after the experiments made upon them, in order to 
ascertain their weight. 
The geranium gave the following results : 
ze ietaupa] 1de | aue | We 
I| Day and night. | 1560 gr. | 1@80 gr. Indoors. Clear. 
II 5 r930 * .| 1440 s Clear, warm 
HI — — 1286 “ “ lear 
IV| Day and night. | 3380 “ | 2880 “ In open air. |Clear. 
V “e 3976." | ET E E à Clear, very warm. 
VI é Foo n poa ée é Clear. 
These results indicate that the amount exhaled at night is 
about the same in the open air as in the house, while the evapora- 
tion in day time is more than double in the former position what 
it is in the latter in the same length of time. It will be observed 
that this plant evaporated more than the weight of the portion 
with exhaling surface in the course of twenty-four hours. It 
should be remarked that this and the previous plant were in the 
flowering stage. 
= Plant No. 3, a fuchsia (F. macrostemma), was a shrubby plant 
-inthe flowering stage; leaf surface estimated at 450 square inches; 
_ height of plant 27 inches; weight of the portion having evapora- 
ting surface 2 ounces; of whole plant, with roots washed and in a 
green state, 4 ounces; complete weight of outfit ready for experi- 
ment, g pounds 15 ounces 360 grains. 
Coincident with the remainder of the experiments, daily obser- 
ations were also made on the average temperature and dew point. 
It should be stated that these latter observations were taken in the 
same medium in which the plant was situated. 
This plant gave the following interesting results: 
Duratio Loss of | Loss by |Avera’e| Average : 
P ean weight by| day, 12 |temper- dew Plate. Weather, 
` jevapora’n| hours. | ature. | point. 
ae Day and night|1810 gr.|1260 gr.| 77.° 61.4° | Indoors. (Clear. 
II i 1800 “ 1240 “ | 72 r = 
Bis “ 1450 “ | 980 “ | 68. | 49.9 | “  _ |Partly cloudy. 
IV « —— laa%0  |1910 * | 63.5 | 49.5 |In open air Cloudy, some rain. 
V He ae = 1536 " ace 50.5 s Clear, partly cloudy. 
Ni} ” 2510 “ |2020 “ | 65. | 49.9 a Clear, windy. 
‘Tt will have been observed that the average temperature was 
higher, and the dew point consequently correspondingly lower 
oy the time of the observations made on this as in the 
