ELECTRICITY. 



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at the other end to the same depth, and connect- 

 ed by a copper wire. The weather was 

 showery, and the growth of all wa.9 rapid. In 

 the course of 30 hours, the galvanised ones had 

 assumed a darker appearance, and were more 

 regtilarly up than the others, and decidedly in 

 advance ; and in the course of a fortnii^ht they 

 were so much forwarder than the others, as to 

 be easily s<^en at a cou.siderahle distance, and 

 were alto£;:fther much higher :uk1 stronger. I 

 am also trying an experiment with some Pota- 

 toes, but they are not up yet. These results 

 have been so satisfactory to me, that I intend to 

 trj- the principle upon an acre of Barley, and 

 am preparing the wires for that purpose ; and, 

 when fuiished, will send you the results. A. 



RoYAi, iNSTiTtmoN, May 16. 

 Reverend E. Sidney on the Electricity of 

 I'lauts, and intluence of Electricity on Vegeta- 

 tion. In introducing the subject of his lecture, 

 Mr. Sidney took occasion to draw attention to 

 the important nature of the inquiry, its high in- 

 terest as a branch of natural science, and the 

 valuable practical results which might possibly 

 be brought to light in its investigation. The at- 

 tention of electricians, he stated, had been drawn 

 to tlie subject so long back as 1746, when a Mr. 

 Maimbray, at Edinburgh, announced that elec- 

 trified plants grew more rapidly and vigorously 

 than those that were not so treated ; about the 

 siune time the Abbe Nollet discovered that elec- 

 trified seeds germinated with increased facility; 

 and these observations were confii-Sied and ex- 

 tended by the experiments of Bertholon and 

 Jalabcrt, the former of whom attributed very 

 marked etlects to the use of electrified water. — 

 The truth of these experiments was supported 

 by some electricians, but denied by others, who, 

 upon repeating them, could not perceive any ef- 

 fect produced on the electrified plants : amongst 

 the latter class stands the name of Sennebier ; 

 but on reading the account of how his experi- 

 ments were performed, it is no longer surprising 

 that he failed to perceive any effect from elec- 

 tricity as he placed the seeds which were to be 

 electrified inside an electrified vessel, a situation 

 in which it is evident they would not be ex- 

 posed to the electric influence. After briefly ad- 

 verting to the more recent observations of Davy, 

 Pouillet, and others, Mr. Sidney drew attention 

 to the recent progress of tlie subject, and the 

 high interest it was at present exciting. The 

 first point which the lecturer insisted on, wa.s, 

 that electricity appears to exercise a powerful 

 influence on growing plants; in support of which 

 he quoted a number of experiments and obser- 

 vations, all tending to .show that plants, under 

 tlie influence of electricity, grow with increa.sed 

 vigor, and more especially when negatively 

 electrified. The manner in which drooping 

 plants have been observed to revive, on the ar- 

 tificial application of electricity, was also no- 

 ticed; and, lastly, the effects which are found to 

 be produced by thunder-storms were described. 

 The rapid growth of plants during thunder- 

 storms might, no doubt, in part be attributed to 

 other causes; but. at the same time, it was a very 

 fair inference that the electric condition of the 

 air had something to do with the phenomena, as 

 such a conclusion was borne out by numerous 

 experiments, on a small scale, made with artifi- 

 cial electricity. Electricity of low, hke that of 

 high tension, has been found to affect germina- 

 ting seeds and growing plants in a remarkable 

 manner; it was noticed bv Davy, that seeds a:er- 

 (219) 



minated more freely at the negative pole of the 

 voltaic battery than at the positive, and since his 

 time numerous experiments have been made, 

 all tending to prove that voltaic electricity pow- 

 erfully affects plants. Mr. Sidney next drew at- 

 tention to the facility with which fresh vegeta- 

 ble matters conduct electricity, in consequence 

 «f the good conducting power of the fluids 

 which they contain; this was illu.strated by plac- 

 ing a small blade of Grass in contact with the 

 conductor of a powerful electrical machine, 

 when it was proved that the whole of the elec- 

 tricity generated by the machine was quietly 

 carried away by the blade of Grass. It was also 

 shown that the pointed forms of the leaves and 

 other parts of plants, combined with their good 

 conducting power, fitted tliem most admirably 

 to receive or disperse electi-icity ; and hence 

 electricians sometimes employed vegetable 

 points in place of metallic ones for those pur- 

 poses. To show this, a large Leyden jar was 

 quickly and silently discharged, by bringing the 

 pointed blades of Grass near its outer surface, 

 and the brass knob at the top. In consequence 

 of the high electric powers of plants, as might be 

 supposed they exerted a marked efi'ect on the 

 electric condition of the atmosphere, .so that when 

 an electroscope indicated abundance of electri- 

 city in the free open air, it indicated none in the 

 vicinity of a tree with pointed leaves. In illus- 

 tration of the good conducting power of vegeta- 

 ble matter, Mr. Sidney .stated that it was impos- 

 sible to give an electric shock to a circle of peo- 

 ple standing on a lawn, as the electricity inva- 

 riably took the shorter and better conducting 

 course through the Grass ; whilst there was no 

 difficulty in giving a shock to any number of per- 

 sons standing in a circle on gravel. 3dly. The 

 apparent adaptation of the vaiious parts of plants 

 to different electrical uses, was pointed out. — 

 Thus, the first leaves of many plants are pointed 

 and acute ; others rounded" or globose. The 

 buds of most plants are pointed, or covered with 

 a strong pubescence. Some plants, more espe- 

 cially tho.sc which grow rapidly, have an im- 

 mense number of sharp points, or pointed hairs; 

 whilst those which grow less rapidly, or are in- 

 tended to meet the variations of the seasons, are 

 less pointed, but often provided with dry thorns 

 or pi-ickles. As plants come into flower, they 

 generally tend more to a globose form ; the flow- 

 er-buds are generally rounded, and the fruit, or 

 seed-vessels, are seldom provided with acute 

 points. It may, therefore, possibly be the case, 

 that though electricity is favorable to plants at 

 one stage of their growth, it is hurtful to them 

 at others, just as is well-known to be the case 

 with light, which is essential to them when full- 

 grown, but is hurtful to them in the embryo 

 state. The general phenomena of vegetation 

 were then considered in relation to electrical 

 agency; It would prove an interesting subject 

 of inquiry, to examine in how far the rise of the 

 sap in spring is influenced by electricity ; it is 

 certain that in spring, and before the leaf-bude 

 are opened, whilst they still retain their pointed 

 form, the air is dry, and in the most fittins state 

 for electrical effects. Mr. Sidney then adverted 

 to the singrular powers which plants have of pre- 

 cipitating moLsture from the atmosphere, an ef- 

 fect which he suggested might pos.sibly be of 

 electric origin, and endeavored to strengthen 

 this view by a number of ingenious artruments ; 

 amongst others, the remarkable cases described 

 by Mr. \Veekes and other electricians, in which 

 showers of ram were brought down by the use 



