470 



ACTION OF THE SALTS OF IRON ON VEGETATION. 



a tlrv or touph cpiJennis, and a thicker tis- 

 sue, "become grceii only after repeated bath- 

 inijs. 



"There are then, under these different re- 

 lations, studiesof iiulividiial and specific de- 

 tails to be made, which will direct us in the 

 application of this remedy to the difTerent 

 forms of vefjetable maladies ; but we cannot 

 doubt the action of the salts of iron, more par- 

 ticularly of the sulphate of iron, on plants af- 

 fected with this diseased discoloration of 

 their green parts, designated as the vegeta- 

 ble chlorosis, nor its influence in re-estab- 

 lishing, in time, the natural color of these 

 organs, (unless the malady has produced a 

 disorganization of its tissue,) and thence, 

 finally, confirming the natural color, in the 

 new parts which may be developed. Un- 

 der this influence and its consecutive 

 changes, we may see the plant recover all 

 the characteristics which indicate sound 

 health. 



" As to the action of the salts of iron on 

 healthy plants, or on those in their natural 

 state, it is much more difficult to determine 

 it by the experiments of the garden, and 

 the results we have obtained are not suffi- 

 ciently distinct to allow us to consider the 

 question as settled. 



*' M. Gris has cited many examples of 

 vegetables and grain, watered with ferrugi- 

 nous solutions, particularly that of the sul- 

 phate of iron, which appeared more vigor- 

 ous and presented a greater weight than 

 analogous plants which had not received 

 these solutions. 



" We have repeated these experiments 

 on seeds sown this spring, both in the open 

 ground and in pots, and, in this instance, in 

 different kinds of earth ; in the open ground 

 we have sown spring corn, oats, peas, beets, 

 buckwheat, cabbages and turnips ; a part 

 of each one of these sowings was watered 

 with a solution of five drams to the quart, 

 and subsequently of a dram and a half to 

 the quart, in order that the leaves which 

 could not escape soaking should not be in- 

 jured. These waterings were repeated five 

 or six times during the months of June and 

 July, without producing any perceptible dif- 

 ference to the sight. 



" We have sown in pots, barley, {Horde- 

 um hezastichum,) oats, {Avena sativa,) pink 



clover, {Trifoliinn incarnatum,) rape, {DraS' 

 sica vapiis,) pei)pergrass, {Lipidum sativum,) 

 buckwheat, {Volygoiium fu^opyruin,) and 

 love-lies-bleeding, (Ainaranthus caiidalus ;) 

 two pots of each one of these plants con- 

 tained the ordinary earth of the garden ; 

 two peat soil ; and two were of siliceous 

 sand ; each pot having a mouth of about 

 seven inches and containing eight or ten 

 roots of each plant. Every other pot was 

 moistened with pure water, and every other 

 residuary one was watered, from time » 

 time, with a solution of 2.^ drams of sul- 

 phate of iron in a quart of water, of which 

 a gill was at first applied to each pot, and 

 subsequently two or three gills. 



" There was, in general, very little dif- 

 ference between the two series, especially 

 of the plants in the ordinary earth ; the 

 plants sown in the heath mould, and espe- 

 cially those in the sand, generally appeared 

 to be stronger when they were watered 

 with the suljjhate of iron solution : this re- 

 sult was quite marked in regard to the 

 buckwheat and cruciform plants. 



" If, then, v.'e are to regard experiment 

 conducted on so small a scale, with some at- 

 tending accidental circumstances of decided 

 importance, it would seem that the action 

 of the sulphate of iron would prove favora- 

 ble on thin and sandy soils; but we cite this 

 result, with our declared restrictions, merely 

 to indicate the interest which more extend- 

 ed experiments might develop in sterile and 

 sandy soils, by means of feeble solutions 

 (.^ or 1 dram to the quart, so as not to in- 

 jure the leaves,) repeated two or three times, 

 and in such quantity that every square 

 yard should every time receive from three 

 to four quarts of the solution. 



" It is evident that, as this part of the 

 question, so eminently interesting in an ag- 

 ricultural point of view, is the least ad- 

 vanced, that renewed experiments are need- 

 ed ; and with these M. Gris has been oc- 

 cupied during the current year. 



" The results of the researches to which 

 M. Gris has devoted himself with so much 

 zeal and perseverance for many years, ap- 

 pear to be these : 



" ]. That the salts of iron, (sulphate, ni- 

 trate, chlorate and acetate,) whether absorb- 

 ed into plants by the roots or the epidermis 



