12 



Galvanic Experiments on Vegetation. 



Vol. IX. 



lono^ed on purpose, the application of elec- 

 tricity must have accelerated the growth in 

 a very rapid manner. 



Many observing farmers will, no doubt, 

 have noticed that vegetation proceeds more 

 rapidly after a thunder storm than after one 

 which shows no electrical phenomena ; and 

 we find, on examining the various formation 

 of the parts of plants, that they are well 

 adapted for the passage of electricity through 

 them, either from the earth or the atmos- 

 phere. Witness the points and serratings, 

 as well as the hairs and down on the leaves, 

 all good conductors, and calculated for af- 

 fording it a silent and easy passage. That 

 this is the case, any one may satisfy himself 

 by a very simple experiment. Charge a 

 leyden jar either by mechanical or chemical 

 electricity — for both are the same, though 

 excited in a different manner — then stick a 

 wire in the ground near a plant, having the 

 upper end pointed ; liold the knob of the jar 

 near, but not to touch, the edge of one of 

 the upper leaves, and let the outer coat of 

 the jar be within an inch of the upper point 

 of the wire in the ground. In a few seconds 

 the whole of the charge of the jar will be 

 silently drawn off through the plant, and the 

 outside coating will have received its com- 

 pensation through the pointed wire from the 

 ground, the equilibrium of the jar being 

 restored without a spark or any other per- 

 ceptible effort. Were the knob of the jar 

 to touch the leaf, and the outer coating 

 brought within what electricians call the 

 " striking distance," a spark would pass, 

 which, were the plant of a very juicy na- 

 ture, as the cucurbita tribe, the shock would 

 burst the vesicules, and the plant would die. 

 A ligneous plant, however, will bear very 

 strong shocks, apparently with impunity; 

 yet, a repetition would, sooner or later, rup- 

 ture its vessels also. 



My first experiment was on some melon 

 plants, in 1842. Only a few plants escaped 

 the fly: through them I passed a shock from 

 a jar containing a coated surface of fifty 

 inches — in short, a pint jar — and the result 

 was, they were all killed the same day. On 

 the aflernoon of the same day, I planted 

 some cucumbers, mixed some salt and man- 

 ganese in thei hill, which was moistened 

 with very dilute sulphuric acid, and a shock 

 passed through each hill. On the following 

 afternoon, three out of the four hills, were 

 up, and on the next morning the whole were 

 up, with most of the seed leaves spread 

 open: by the eleventh day, the plants had 

 two rough leaves, and as the day was very 

 warm and dry, I soaked the hills with water 

 very slightly acidulated with sulphuric acid, 

 about one quarter of an ounce to a gallon. 



I then gave some plants in each hill a shock, 

 leaving only two in each, and to these I 

 gave a silent charge. Those which re- 

 ceived the shock all died, while the others 

 continued as thrifty as before, till the 24th 

 day, when I moistened the hills with pure 

 water, as they were th,en beginning to 

 open their blossoms, passed a silent charge 

 through two hills, and left the others. The 

 first few blossoms were all males; no fruit 

 blossoms appeared, or rather opened, until 

 the 28th day, when the four hills were 

 moistened with acidulated water, and a si- 

 lent shock passed through one hill only, the 

 others having none. I was at this time 

 fi'om home a few days, and on my return I 

 found two cucumbers on the hill which re- 

 ceived the last charge, about five inches 

 long and one and a half in diameter, which 

 were cut and eaten. This was on the 37th 

 day after planting, and the flavour could not 

 be said to be any thing difierent from that 

 of the same variety — white spine — grown 

 in the usual manner. I found that, during 

 my absence, my boys had taken the other 

 hills under their charge, and in the course 

 of their quick and energetic treatment, they 

 were all killed before I returned. I may 

 remark, that the cucumbers did not run 

 much to vine, no runner having extended 

 so far as two and a half feet, which is rather 

 a strong contrast to the result of the same 

 treatment of pumpkins in the following sea- 

 son. I planted five seeds of a new variety 

 of pumpkins among some potatoes in 1843, 

 giving them precisely the same treatment 

 as the cucumbers had the year before, but 

 only gave them two charges — one at sow- 

 ing, and one when they had two rough 

 leaves: they were then left to themselves, 

 when I Jiave reason to believe one of the 

 plants died, leaving only four, which, from 

 their luxuriant growth, entirely covered the 

 square in the garden, 57 feet long and 30 

 feet wide, in which they were planted : be- 

 sides, every day or two, some runners cross- 

 ing the walks had to be cut off. With all 

 this luxuriance, not a blossom was seen on 

 them the whole season ; and I may also re- 

 mark, that under their shelter the grubs 

 had destroyed the potatoes, which were not 

 worth digging, as nothing but thin shells of 

 the outside were left. 



I also last season, 1843, made some ex- 

 periments with dahlias; but before the silent 

 charge vroi'.ld pass freely through them, it 

 was fijund necessary to water tiie plant all 

 over, if the day had been very dry and hot. 

 I will mention one in particular. On the 

 10th of September. I took oflT a cutting 

 about a foot long, planted and shaded it till 

 it struck; on the evening of the 15th it 



