PHYSICAL AND METEOROLOGICAL RESEARCHES. 

 Effect of electricity on the germination of beans. 



213 



This experiment shows that the germination was more rapid in the 

 electrified seed and also that a greater number had germinated. We 

 repeated the experiments in 181)5 and 1896 on peas and beans with the 

 following results: May 11, 1895, the same number of seeds were placed 

 in each plate. No difference could be seen during the time of germina- 

 tion. The peas bloomed June 16; the fiowers at that time were more 

 numerous and the plants better developed in the electrified plates than 

 in those without. The beans bloomed July 2 over all the plates. The 

 growth of the beans was better in the electrified portion. The peas 

 were gathered twice and gave the following results: Average of elec- 

 trified portions, 941 gm. ; check, 820 gm. Part of the beans were gath- 

 ered twice and yielded: Electrified, 2,900 gm.; check, 2,250 gm. For 

 the other parts there was but one harvest, which yielded as an average 

 for tbe electrified portions 1,410 gm., and check, 1,445 gm. One of the 

 electrified portions gave a yield of 375 gm. less than the check. The 

 results of these experiments show that the parts electrified by piles 

 yielded a harvest from 20 to 28 per cent greater than the natural one. 



OBSERVATIONS ON TREE TEMPERATURES. 



To solve some of the questions relative to tree temperatures, elbow- 

 thermometers were constructed, the bulbs of which were inserted in the 

 heart of the tree. Numerous observations made in 1894, 1895, and 1896 

 permit the following statements : The internal temperature of trees fol- 

 lows that of the air. The temperature of the air is led into the interior 

 parts, and this transmission is more or less rapid according to the diam- 

 eter of the tree and the conditions of the tissues. The temperature 

 varies with the diameter of trees of the same species and exposure. In 

 conclusion, conductivity differs according to species. The sudden vari- 

 ations of the temperature in the interior of the trees are avoided by the 

 modification of the sun. 



The foregoing are summarized statements of the researches which 

 have been made at the agricultural-climatologic station at the observa- 

 tory of Juvisy. The author believes that much remains to be discov- 

 ered in the lines indicated. 



