EXPERIMENT ON GRAPE-VINES. 243 



they would meet with a constant supply of nourishment. A 

 kind of vegetable instinct evidently controls the feeders to plants, 

 and enough push out to secure each distinct element in exact 

 proportion to its wants ; and the less the distance they travel, 

 the less the vital force consumed in urging onward the nutri- 

 tious principle. 



The growth of wood the first season was strong and vigorous, 

 and that of the past summer so extraordinary, that I had the curi- 

 osity to collect the wood that pushed out and matured from single 

 buds and weigh it, and the amount was found to be one hundred 

 and seven pounds. Analysis of a portion of the leading shoot 

 from one of the vines, basing the estimates upon ten gramms, the 

 amount employed in the examination, gave as the quantity of 

 water held in association sixty-one pounds ; combustible matter, 

 forty-four and a half; ash, one and a half pounds. The ash 

 contained of potassa, twenty-nine parts in the hundred ; phos- 

 phate of lime, nineteen ; carbonate, thirteen ; soda, three ; mag- 

 nesia, four, and small quantities of iron, silex, &c. The parts 

 are given in round numbers, as for the purposes had in view 

 scientific accuracy of statement is unnecessary. The wood, 

 therefore, cut away at the fall pruning carried off nearly eight 

 ounces of potash, more than five ounces of phosphate of lime, and 

 of lime and carbonic acid nearly four ounces. The subtle 

 chemical agencies at work in the soil to render soluble and 

 digestible so large amounts of mineral salts, how difficult to 

 comprehend ! and then how amazing the amount of mechanical 

 force exhibited by the vines starting from tender buds, capable 

 of sustaining at maturity more than sixty pounds of water, and 

 keeping it in motion through the pores. 



It is fairly to be inferred from the results of this experiment 

 that the luxuriant and healthy growth was due to the generous 

 supply of food precisely adapted to the wants of the vine, and 

 that the teachings of chemistry, as relating to the structure and 

 appetite of vines, are worthy of regard. 



What course is obviously to be taken when from repeated 

 croppings the grape clusters fail to appear ? Shall we tear up 

 our vines, as do .many, and entirely remove the contents of the 

 border as waste matter, and at much expense form a new one ? 

 Drenching with farm-yard manure from year to year has failed 

 to restore to full fruitfulness ; and why ? Because it does not 



