432 I'LANTS AND THE ATMOSPHERE. 



succeeded in iDtrodueing a small and very sensitive thermometer, first among the 

 stamens which were heated 22 degrees, and afterwards among the carpels which 

 produced an action only half as great. The other parts of the plant did not 

 betray any special action. By dint of care and watchfulness, Saussure surprised 

 four Ar'ims at the moment of their rise in temperature, and placed them under a 

 bell glass filled with air. Immediately, the sides of the glass became covered 

 with mist, and a great absorption of oxygen, with a corresponding production of 

 carbonic acid, took place. Both in its 'chemical action, and in the energy of that 

 action, the plant might have been compared to a rat. Another time, Saussure 

 dissected the plant into its different parts which he studied separately: the sexual 

 organs consumed 132 parts of oxygen and the rest of the flower only 80. 



After fertilization the fruit begins to dfvelope itself and the plant to nourish it. 

 Not only does the latter furnish it with the matter accumulated in its tissues, but 

 also gives it a still greater quantity which the fruit consumes, by a species of 

 respiration peculiar to itself. The whole of plant life thus seems to be exclusively 

 devoted to the accomplishment of this last duty, namely, that of nourishing the 

 fruit. By this labor, it impoverishes itself; beet and sugar-cane expend all the 

 sugar which they contain, all plants exhaust the stores they have accumulated 

 from the time of their youth, and when the truit is ripe, tiie plant, if an annual, is 

 reduced to a dried up skeleton, and, if perennial, remains torpid during the quiet 

 of winter so as to recover strength and begin next year its provident function. 

 The survey which has now been made, contains, besides the questions of detail 

 which I desired to examine, a great truth with which I would conclude, namely, 

 that our earth is not adequate to itself, since force is wanting to it ; but it receives 

 this from the sun, which pourffthe active principle upon it in the form of rays. 

 Thanks to this gift, life is transmitted to the globe under two antagonistic forms, 

 vegetable life, which accumulat'S force by creating organic matter, and animal 

 life, which expends and dissipates what the sun furnishes and what plants absorb 

 and preserve. 



J. C. 



