New York Agricultural Experiment Station. 355 
upright as the garden varieties do. None of the plants have 
approached, either in shape of leaf or in habit, the cultivated varieties, 
the chief change that has taken place, aside from size, being in the 
greater or less dissection of the leaves. The result of one year's 
observation upon such a question has little value further than to direct 
additional attention to an important subject. The trial should be 
carried through several seasons with observations upon the same 
individuals, and supplemented by ascertaining the constancy of the 
characters in plants raised from seed through several generations. 
Constant Temperature Apparatus. — Considerable time has been given 
to perfecting an apparatus for keeping a constant high temperature 
in a space large enough to permit of the introduction of one or two 
germinating pans for testing seeds. The question to be decided by 
the apparatus was the highest point at which different seeds will 
germinate, taking the element of time into consideration. This 
required some means of keeping a temperature that would not vary 
more than one degree, or less if possible, for a week or two at a time, 
or even longer. The chamber had to be heated with a kerosene name, 
as gas was not available, and so none of the usual forms of heat regu- 
lators could be used. The machine as finally arranged, and which 
reached a fair state of efficiency, consisted of a chamber, something 
more than two feet cube, surrounded by dead air spaces, with a copper 
reservoir of water in the bottom, so connected by pipes with a jacket 
about the flame of a kerosene lamp as to secure a flow of water. Cold 
air for lowering the temperature of the chamber when too hot was 
taken from the bottom of an ice chest placed higher than the chamber 
in order to secure a flow of air. Valves were placed in the cold air 
conduit, in the top of the chamber, for escape of hot air when cold air 
was admitted at the bottom, and in the top of the ice chest, to allow 
as much air to pass in as was drawn off to supply the chamber. These 
three valves were automatically opened and the lamp turned down 
when the temperature of the air in the chamber reached the highest 
permissible point, and were closed and the lamp -turned up again when 
it dropped to the lowest point — the variation being a degree or less. 
The power for making these changes was secured by means of a clock 
work having a heavy spring, reinforced to any extent with a weight 
and system of pulleys. The clock was set in motion by an electro- 
magnetic connection with a vibrating thermostat placed in the cham- 
ber, regulated to the desired degree of temperature. It was found 
that, although no fault could be detected in the apparatus, there was 
still an uncontrollable although slight variation of temperature disturb- 
ing the nicety of the results, doubtless to be ascribed to the great 
