221- 



Protection of Floisoers 



to the Society of Arts, dated as far back as June, 1839, upon the same 

 su ject . — ^^ ^^^j^ ^^^ Lowgate, June 26. 1839. 



" You will receive herewith, carriage paid, an apparatus of my invention, 

 which, if you will have the goodness, at an early period, to lay before the 

 Society, in order that those who consult your valuable work may have the 

 benefit, I shall be greatly obliged. j ur o «r 



At this season, any invention that will perfectly secure our dahlias, or 

 other more delicate plants, from the attacks of those voracious pests ot the 

 flower-garden, the Mollusca, must be highly acceptable. No one has had to 

 contend with a more formidable array of this class than myself, particularly 

 the genera Helix and Limax of Linnaeus; and I am happy to intorm you, 

 that the galvanic plant-protector above mentioned, and sent herewith, torms an 

 effectual barrier against these formidable enemies. 



I have had them in use in my own garden for twelve months, and can 

 assure you that, although during that period plants on all sides have suttered 

 from these creatures severely, not a plant has been injured that has had the 

 protection of the galvanic circle. . 



The annexed drawing and description will exhibit the apparatus and explain 

 its operation. The galvanic plant-protector consists of a taper or conical ring 

 of zinc, of the following dimensions: 6 in. diameter '*' 



at top (« b), the bottom (c d) 4| in,, and the height 

 (« c) 4 in. The top edge is flanged off about a quarter 

 of an inch, and cut into numerous zigzag or van- 

 dyked points, as represented in the drawing. Im- 

 mediately under this pointed flange another ring, but 

 of copper {E F), is neatly fitted, being exactly of the 

 same taper as the former, and full 1 in. broad {b F), 

 supported in its place by dots of solder in three or 

 four places of its circumference : these dots are repre- 

 sented by the marks z z. Such is the apparatus ; its 

 operation is thus : — The bottom of tlie zinc ring 

 (C d) being pressed into the soil until the lower edge 

 of the copper ring is about l^in. above the surface, 

 the Mollusca may crawl up the zinc with impunity, 

 but, on coming in contact with the copper, will receive 

 a galvanic shock, and immediately turn away, or fall to 

 the ground. I have repeatedly watched them, and 

 have observed they were extremely cautious in ap- 

 proaching a second time. I prefer the vandyked edge to a plain one, for this 

 reason, if the larger of this tribe attempt to stretch across and above the 

 copper belt, avoiding contact, they would be incapable of holding by the points. 

 In fixing the galvanic plant-protector, care must be taken to enclose within 

 the ring the rods, with such plants as require them, as represented m the 

 drawing, otherwise the Mollusca would find a ready road to the plant by tlie 

 rod. The apparatus acts in wet or dry weather, and is therefore always in 

 action. Its appearance in use is like a flower-pot, and its cheapness, utility, 

 and durability must insure its general adoption, ^ 



I believe the same principle may be applied to walls ^ a- 

 for the protection of fruit trees, straps of zinc and ^ 

 copper being judiciously placed along the vvall, and ^ 

 around the stem of each tree; tlie best position, in my 

 opinion, would be an angle of 45° with the wall. Sup- 

 pose a b, in the annexed figure, to represent the sec- 

 tion of a wall, c d the strap of zinc and copper, e b 

 the ground line ; the angle c d b, I think, should be 

 about 45°. In this arrangement the copper should chp 

 the edge of the zinc strap, c. 



In addition to the security from snails, &c., I believe 



Fig. 35. Galvanic Plant. 

 Protector. 



Fig. 36. Galvanic Protector 

 for Fruit Trees on Walls. 



