NEW ENGLAND FARMER. 



407 



ricultural chemists now agree, in error. To change 

 the volatile carbonate of ammonia, more ready to 

 Sy away than riches, when they have wings, into 

 a s tluble sulphate, and thus to diffuse it through 

 the s tit, and to hold it in readiness for the plants, 

 to lie an important, but not as Liebig thinks, 

 the only office of plaster. 



B aissingault thinks that plaster acts purely and 

 solely as lime. He believes that in the presence 

 of organic matter in the soil, it is converted into 

 aulphuret of calcium, and then, by means of car- 

 bonic acid in the water surrounding it, into sul- 

 phuretted hydrogen and carbonate of lime ; and 

 he supposes that the greater value of the carbon 

 ate of lime thus formed is owing to the exceeding 

 fineness with which it is divided, so as to be readi- 

 ly dissolved in the carbonated moisture of the soil, 

 and thus to enter the roots of plants as food. 



A potent argument for this theory is, that 

 plaster, as a general rule, benefits plants whicl 

 abound in lime, whether they contain a very 

 large share of sulphuric acid or not. But a fatal 

 objection to the theory, that plaster acts solely as 

 lime, is found in the fact, that it acts most favora- 

 bly in some plants which abound in sulphuric acid 

 and contain comparatively little lime. Indian 

 corn, for instance, carries off much more sulphuric 

 acid than lime, and yet is confessedly benefited by 

 plaster. 



Sir Humphrey Davy's theory amounted to little 

 more than that certain plants cannot be devel- 

 oped in their perfection without sulphuric acid and 

 lime, and that the office of plaster is to feed them 

 with these elements. He would have us ascertain 

 by careful observation and experiment, which are 

 the plants to be benefited by plaster, and to use 

 it accordingly. 



TherS is something peculiar in the views of each 

 of these men. Girardin and Breuil believe that 

 no good effect comes from plaster in the way of 

 gathering moisture or of hastening the decomposi- 

 tion of organic matter. They, in common with 

 Sir Humphrey Davy, believe that plaster feeds the 

 plant on its own elements. Boussingault believes 

 that it acts simply as lime, feeding the plant on 

 this element only. Liebig holds, that acting in- 

 strumentally, and not directly furnishing its own 

 elements to plants, it feeds them on ammonia, 

 that is, seizes and holds for their use the am- 

 monia that otherwise would escape. 



Partly as guided by these rather discordant au- 

 thorities, partly led by my own experience, and 

 more by consulting sound, observing farmers, I 

 come to the following conclusions, which, however, 

 I present rather with the hope of eliciting discus- 

 sion, than with the wish that they should be 

 adopted. .The adoption of them could afford me 

 no satisfaction, farther than as it might operate as 

 an evidence of their truth. 



1. In its transformations and in some or all of 

 its subsequent combinations, plaster attracts mois- 

 ture from the air and from the subsoil, and so 

 withholds it from evaporation, that the plants can 

 the better endure a drought. 



2. The lime of plaster, in its transition and in 

 its subsequent combination with carbonic acid, 

 favors the decomposition of organic matter, and 

 thus hastens its conversion into available food for 

 plants. 



3. By means of a double decomposition with 

 carbonate of ammonia, forming soluble sulphate of 



ammonia and carbonate of lime in a state of ex- 

 ceeding fineness, it prepares its own elements for 

 reception by the plants, and at the same time 

 saves for their use the ammonia, which would 

 otherwise escape. 



If the view I have now taken is correct, the 

 points into which the practical farmer needs to look 

 are these : 



1. Whether his land is well drained, or is suffi- 

 ciently dry by nature 1 If not, the first action I 

 have ascribed to plaster would be of no benefit, but 

 rather injury. Plaster would either be wholly in- 

 operative, or it would render the land still more 

 wet, cold and sour. 



2. Whether the land is supplied naturally or by 

 manuring — by carrying on manure, by the drop- 

 pings of cattle, or by the plowing in crops with 

 organic matter ] If not, the second action I have 

 ascribed to plaster cannot take place. It cannot 

 decompose organic matter, where there is none to 

 be decomposed. Nothing is more certain than 

 that plaster cannot operate well but in conjunction 

 with animal and vegetable manures. 



3. Whether his land already contains sufficient 

 of sulphuric acid and lime; or whether, for any 

 other cause, it is of a kind that refuses to be bene- 

 fited by plaster 1 This he can ascertain by pro- 

 curing a chemical analysis ; or better, as I think, 

 in the present state of things, by experiment and 

 careful observation. If he try plaster on a partic- 

 ular quantity of land and find its effects good, he 

 may safely repeat the operation on the same, and 

 extend it to similar land. 



Before venturing largely in the use of this or 

 any other fertilizer, to which he has not been ac- 

 customed, he should ascertain as far as possible 

 what have been its results on lands near and sim- 

 ilar to his own. With such precautions there is 

 very little danger of loss from the use of plaster 

 far more extensively than at present it is used. 



MASSACHUSETTS STATS BOARD OF 

 AGRICULTURE-- 1852. 



LIST OF MEMBERS FOR 1852. 

 Members ex-officiis — His Excellency the Govern- 

 or ; His Honor the Lieut. Governor ; The Hon. 

 Secretary of the Commonwealth. 



Appointed by the Governor and Council — Ed- 

 ward Hitchcock, Amherst ; Marshall P. Wilder, 

 Dorchester; Nathaniel Wood, Fitchburg. 



Chosen by the several Agricultural Societies — 



Barnstable County, Charles B. II. Fessenden. 



Berkshire " Stephen Reed. 



Bristol " J. H. W. Page. 



Essex " John W. Proctor. 



Franklin " James S. Grennell. 



Hampden " Francis Brewer. 



Hampshire " John A. Nash. 

 Hampden, Franklin ) j osep h Smith. 



and Hampshire, 

 Massachusetts, 

 Middlesex County, 

 Housatonic, 

 Norfolk County, 

 Plymouth ' ' 

 Worcester " 

 Worcester West, 



John C. Gray. 

 Simon Brown. 

 Joshua R. Lawton. 

 Benjamin V. French. 

 Seth Sprague. 

 John W. Lincoln. 

 (Vacant.) 



