INFLUENCE OF ELECTRICITY ON VEGETATION. 85 



plants of all kinds are known to grow with remarkable vigour. 

 He however attributes even more marked effects to a constant 

 but feeble electric condition of the earth, which he conceives 

 promotes vegetation on a large scale, just as feeble artificial 

 electricity has been proved to do in various experiments. Simi- 

 lar observations are also made by the Abbe Mann, 1774.* 



In 1773 the Abbe d'Everlange de Witry communicated to 

 the Brussels Academy of Sciences a paper on the influence of 

 electricity on the fluids of vegetables.f After speaking of the 

 effect of electricity on fluids moving in capillary tubes, and quot- 

 ing tlie experiments of Nollet and Jallabert, he expresses sur- 

 prise that the views deduced from their results have not been 

 more generally adopted, and attributes this to the contrary re- 

 sults obtained from imperfect experiments on diseased or un- 

 healthy plants ; he appears to have no doubt that electricity does 

 affect the circulation of the sap of plants as well as that of the 

 blood in animals, and enters at some length into the subject of 

 its application in the cure of disease. The same year, M. I'Abbe 

 Bertholon communicated to the academy at Beziers some obser- 

 vations on the influence of meteors, lightning, and the rain of 

 thunder-storms, on the germination of seeds and growth o 

 plants. 



An announcement was made in 1775, by C. H. Koestlin, in his 

 ' Dissertatio physica experimentalis de Effectibus Electricitatis in 

 quaedam corpora organica,' that negative electricity was detri- 

 mental to vegetation ; both animal and vegetable life being 

 retarded by negative electricity. This appears to be the first dis- 

 tinct observation as to the diflferent influence of negative and 

 positive electricity, as the preceding experiments seem all to 

 have been made with positive electricity alone. The following 

 year M. Bertholon read before the Academy of Sciences at Paris 

 an account of a series of experiments on the conducting power 

 of plants for electricity, in which he showed the great differences 

 which exist between different plants, those, generally speaking, 

 being the best conductors which were the most succulent or 

 contained the largest quantity of moisture. 



In 1779, the Count de Lacepede,| in his book on Electricity, 

 describes some experiments which he had made on vegetables, 

 observing that invariably, on electrifying a plant, he found it 

 grow, or increase, with more vigour than usual, and that the 

 germination of seeds, and sprouting of bulbs placed in water, was 

 always hastened in a very decided manner by electricity. The 



* Memoires de rAcademie de Bruxelles, t. ii. p. 1, 46. 



t Ibid., t. i. p. 181. 



X Essai sur I'Electricite' Naturelle et Artificielle, tome ii. p. 166. 



