224 CALCAREOUS MANURES— APPENDIX. 



"No. 9. See foregoiriEj, pa^e 218. Having sulphuret of iron in powder, or minute 

 crystals;" [taken from 14 feel below the beach, in E.] 



Carbonate of lime ..... 2.350 



Bi-sulphuret of iron 5.821 



Sulphate of lime 2.309 



(Carbonate of magnesia not found.) 



'• No. 10. Several thin layers of compressed shells. 1 to 3 inches thick," [contained in 

 stratum 72.] 



Carbonate of lime - - - - - 56.00 

 Phosphate of lime 0.84 



No. 2. [Z)] from 4 feet lovrer than number 1, was examined with results similar to 

 1 and 3. 



No. 4. [D] from 4 feet below beach, and half a mile from number 1, was found to be 

 rich in sulphate of lime and to contain bi-sulphuret of iron. 



No. 5. [D] "From another spot, and has been exposed to the weather from last winter 

 to June on the field where applied as manure." Is richer than No. 2 or 4 in sulphate 

 of lime, but inferior to either in bi-sulphuret of iron. It likewise affords more sulphate 

 of alumina than any sample examinecl. 



" No. 11. The clay at 16 to 18 feet deep ;" [supposed when selected to be the poorest 

 part of stratum £.] 



Carbonate of lime - - - 1.45 



It is rich in sulphate of lime, and has traces of sulphate of alumina, and bi sulphuret 

 of iron. 



It is to be kept in mind that in these analyses no account is taken of such sized crys- 

 tals of sulphate of lime as readily meet the eye, or of large fragments of shells, the 

 occasional presence of both which must often essentialy enhance the gypseous and cal- 

 careous contents of these samples. The proportions in which Ihey may occur at different 

 depths and localities can readily be deteimined, however, by the practical agriculturist. 

 The same may be said of the phosphatic ingredient so far as the teeth and bones of fishes 

 are concerned. 



If we assume the average proportion of bi-surphur.°t of iron in these earths to be 2 

 per cent., and suppose the whole of the sulphate lo become oxidized, it would give rise 

 to 2,722 per cent, of sulphuric acid ; to saturate which would require 1.905 of lime, and 

 thereby pioduce 4.627 per cent, of (anhydrous) sulphate of lime. But 2.722 of lime 

 would demand 3.383 per cent, of carbonate of lime in the soil. Now in the three ana- 

 lyses (Nos. 3, 6 and 9) made, the bi-sulphuret of iron, by average, equals 3.649 per cent., 

 and the carbonate of lime in the same equals but 1.47S per cent. — a quantity too small 

 for the saturation of the acid, even after a liberal allowatice is made for the increase of 

 calcareous matter from the occasional presence of large fragments of shells. 



It would therefore appear to be an obvious deduction from these inquiries, that dress- 

 ings of lime, and especially of calcareous bands, like No. 10, should be employed in con- 

 junction with the green-sand soil. 



Having now replied in the best way I am able to your various inquiries, I leave it for 

 you to make such other practical inferences from the inlbrmation afforded as in your 

 more experienced judgment it may seem to authorize— and remain, very respectfully, 

 your obedient servant, Ch.irles Upham Shepabd. 



Edmund Ruffin, Esq , Petersburg, Va. 



The specimens numbered above 1,2,3, were from one locality, and of 

 earth which was u.$ed as manure for clover of this year, with effect as 

 great as any ever known on marled land ; and with no certain benefit 

 on an adjoining space, (also in clover,) of the same soil naturally, but 

 not marled. Numbers 4, 5, and 6, were from the pit dug in the beach, 

 half a mile distant, apparentl}'^ similar to each other, and to the preceding 

 specimens. All tliese are of the dark stratum (D) richest in green-sand, 

 (except the lowest, E,) and all before rated by me as containing 50 per 

 cent, of the pure granules. Professor Rogers stated the same to contain 

 60 to 70 per cent. (See F, Register, vol. ii., p. 750, and 2d edition of 'Es- 

 say on Calcareous Manures,' p. 1 16.) Even if leaving the green-sand out of 

 consideration, and out of the estimate of value, there would still remain 

 enough of active manuring principles to produce a large share of all the 

 beneficial effects which I have found from the use of this earth ; and I have 



requested, and was so directed. It is therefore that the contents of bi-sulphuret of iron, car- 

 bonate of lime, and sulphate of lime are not stated of No. 1, as in No. 3. — E. R. 



