632 



FARMEllS' KEGISTER-GYPSUM— BEViiiW. 



attention to this question, and from chemists, as well 

 as from practical farmers. 



In the remarks just referred to, we stated from mem- 

 ory only, that gypsum was soluble in about 600 times 

 its quantity of water. Davy and Cleaveland, both 

 state the quantity to be 500, and Thomson, 460 times 

 the quantity of gypsum dissolved — cold water being 

 always understood. 



A statement of the component parts may be new 

 and useful to many readers. Sulphate of lime, or 

 gypsum in a perfectly pure state, consists of the fol- 

 lowing proportions : 



Sill. acid. Liinc. Water. Parts of 



According to Gypsum. 



Davy, - - - - 75 55 34 make 164 

 Thomson, - - - 100 72.41 53.8 228.21 



Bergman, (quoted 



by Cleaveland,) 46 32 22 100 



According to all of these aulhoritie.<<, it will be seen 

 that the lime is less than one-tliird of the whole quan- 

 tity of gypsum, and considerably less than the amount 

 of sulphuric acid with which it is combined. 



As presented by nature, the purest gypsum is seldom 

 free from some small contaminations of carbonate of 

 lime, alumine, silex, and oxide of iron — and these 

 substances enter more largely into all the gypsum com- 

 monly used as manure — though not to so great an ex- 

 tent as to have any considerable effect in lessening its 

 strength — or atiecting the value of the stone, unless by 

 rendering it more difficult to be pulverized. The fo- 

 reign substances in the gypsum of commerce, (the 

 carbonate of lime especially) often serve to render it 

 a better cement after calcination — as a proportion of 

 quicklime is necessary for tins purpose. 



The last No. (for October 1334,) of the Jnnalcs de 

 f Agriculture Tranx^aise, wh\c\\ has been received since 

 the foregoing remarks were in type, contains a pas- 

 sage which shows that the effect of burning gypsum to 

 reduce it for manure, has engaged attention in France 

 — where however, the manure operates much less 

 powerfully than in the United States. One of the 

 premiums offered by the Sociefe roijale elcenirale d'ag- 

 ricullure du dcpartcmenl dc la Seine-Inferieure, for the 

 year 1836, is the following: 



"To determine the best method, and the time most 

 favorable for plastering clovers and plants for forage, 

 and under what circumstances the preference ought 

 to be given to plaster burnt, or plaster not burnt. The 

 prize will consist of a medal of gold, of the value of 

 150 francs." 



[It is altogether unknown to us who is the author of 

 the following concise review — but he is evidently one 

 whose modes of thinking and of investigation are such, 

 that his approbation must be highly prized where be- 

 stowed, and his strictures allowed their full and proper 

 weight. It is not only for these reasons that the arti- 

 cle is here republished, but becatise the reviewer has 

 directed his readers' attention particularly to some of 

 the novel positions in the Essay, which, if true, cer- 

 tainly are of high importance, and which if unfounded, 

 may be, and ought to be, overthrown.] 



From the Genesee Farmer. 



"essay on calcareous manures." 



This is the title of a duodecimo volume of 242 

 pages, publislied more than two years ago, by 

 Edmund RuHlii, editor of the Farmers'' Register 

 in Virginia. It is more ptarticuhiHy designed for 

 the Tertiary Formation of the maritime states; but 

 we have no hesitation in saying fliat it ought to be 

 read by every farmer who wi.slies to undorstand 

 the nature of manures, and to know how to ajiply 

 them to the best advantage. It is an original 

 work oi" great merit. The author is not a mere 

 theorist, jjroposing plans for others to fijliow, Imt a 

 practical larmer who has thoroughly incpiirod mto 

 the causes of the sterility that has long over.«pread 

 the tide-water districts; and who has led the Avay 

 in a course of improvements which must material- 

 ly change the condition of that country. 



f lis chemical experime.ils on various soils have 

 produced some very unexpected and surprising re- 

 sults. For instance: he finds a total absence of 

 calcareous earth in all their poor soils, and also in 

 many rich soils: and it is particidarly worthy of 

 notice that some of these specimens were obtained 

 in the near vicinity of Umestonc rocks. Our au- 

 thor says, "before the first of tl;ese trials w^as 

 made, I supposetl (as probablj' most other persons 

 do) that limestone soil was necessarily calcareous,* 

 and in a liigh degree." His experiments have 

 shown however, that this is a mistaken nolion. 

 One sample was taken from a piece of land so 

 roclcy Avith limestone as to be unfit for the plough, 

 and yet one thousand grains of the soil yiekled 

 only one grain of calcareous earth. Various other 

 specimens have shown a total destitution. Brown 

 loam from the Sweet Spring Valley, remnrl<ab]e for 

 its extraordinary productiveness and durtibility, 

 which must have been often covei'ed and saturated 

 with mineral Avaters holding lime in solution — 

 yielded not a particle of calcareous earth. The 

 same result was obtained from various soils, some 

 lying on the surface of limestone; others taken 

 from between masses of that rock; and our author 

 after detailing the particulars, remarks: "thus it 

 appears that of nineteen specimens of soils, only 

 four contained calcareous earth, and //tree oi' these 

 in exceedingly small proportions. It should be re- 

 marked that all these were selected from situations 

 which from their proximity to calcareous rock, or 

 exposure to calcareous waters, Avere supposed 

 most likely to present highly calcareous soils. If 

 five hundred specimens had been taken without 

 choice, from what are commonly called limestone 

 soils, the analysis of that whole number would be 

 less likely to show calcareous earth, than the fore- 

 going short list." 



We confess these results were new to us; and 

 our curiosity was excited to ascertain if the ricli 

 limestone lands of the Genesee country were in 

 the same condition. On selecting specimens from 

 an old field, at the different depths ol' four and se- 

 ven inches, which we should not hesitate to call 



* The term "calcareous" should be limited and re- 

 stricted to carbonate of lime, lexicographers to the 

 contrary notwithstanding. We are suppoited on tliis 

 point by minoialogisls Avho know the importance of 

 precision in language, and who use the terms calca- 

 reous alabuslcr and gi/pseous alabaster, altoough the 

 base of each mineral is lime. — Gen. Fak. 



