a©6 



THE SOUTHERN PLANTER. 



gave no increase, and Liebig's own patent 

 wheat manure failed. If, moroovcr, sulphate 

 <jf ammonia acts merely as a solvent of phos- 

 phates, &c., how docs it happen that the 

 large amount used on some of the turnip plots 

 is attended with little or no increase, while 

 soluble phosphates artificially applied, give an 

 astonishing increase. 



It is impossible to answer these questions, 

 and accordingly Liebig endeavors to show 

 that the increase of turnips, from an applica- 

 tion of superphosphate of lime, is not due to 

 -<4he soluble phosphate of lime which it con- 

 tains, but to the sulphate of lime necessarily 

 associated with it. 



English fanners will be glad to learn that 

 It is simply the sulphate of lime the superphos- 

 phate contains that benefits their turnip crop, 

 &nd that they can obtain the same effect very 

 uraeh cheaper from gypsum or plaster. We 

 ii&ve no doubt that half a million dollars 

 worth of superphosphate was applied to the 

 turnip crop of England last year, the greater 

 portion of which might have been saved by a 

 Knowledge of the fact discovered by Professor 

 Lie big ! T 



Some will ask on what evidence our author 

 "bases this opinion. We answer, on one sol- 

 itary result, taken from Mr. Lawes' experi- 

 ments — a result in direct contradiction to the 

 general indications of the investigation, and in 

 opposition to the results of other experiments 

 on turnips, with superphosphate, sulphate of 

 lime and sulphuric acid— -a result, in short, 

 which is simply a typographical mistake.— 

 Liebig says : 



" Alike plot in 1845, which received 12 cwfLof 

 gypsum, (residue from the preparation of tartaric 

 acid, ) and -10 cwt. of rape-cake, yielded 18 tons, 1 

 aewt. of turnips, six Um& irwre. than those fields on 

 which phosphoric acid was employed. * * What 

 strange results do these facts offer, — in what in- 

 comprehensible contradiction do they stand to the 

 views of Mr. Lawes." 



On referring to our copy of Mr. Lawes 7 pa- 

 per, we found a marginal note, made years 

 ago, stating that the 18 tons, 1 cwt., should 

 foe 10 tons, 1 cwt. It is much to be regretted 

 that this mistake was not marked in the copy 

 sent Professor Liebig ; or that he did not dis- 

 cover the error, as he might have done by re- 

 ferring to the tables on the two following pa- 

 pages. Few will be surprised, considering 

 the immense amount of tabulation in Mr. 

 Lawes' papers, that a printer, should in one 

 instance, place an 8 instead of a 10, but it 

 will astonish many to find t^iat on this single 

 mistake, Liebig should adopt a view which is 

 not only opposed to the general indications of 

 the whole series of experiments, but is also at 



variance with the experience of every farmer 

 who has used superphosphate of limo and sul- 

 phate of lime of lime as a manure for 



turnips. 



This error corrected, the opinion based upon 

 it falls to the ground, and with it the idea that 

 the beneficial effect of sulphate of ammonia 

 on wheat is due to its rendering the phosphates 

 of the soil soluble. Soluble phosphates great- 

 ly increased the turnip crop, but the same sol- 

 id)U phospliates, on similar soil,' did not in- 

 crease the wheat crop ; sulphate of ammonia 

 did not increase the turnip crop, but did great- 

 ly increase the wheat crop ; therefore sulphate 

 of ammonia does not act simply in furnishing 

 to the wheat plants soluble phosphates. 



Mr. Lawes repeatedly alludes in his papers 

 to the fact that though the increase of wheat 

 over the unmanured plot was in pretty direct 

 ratio to the quantity of ammonia applied to 

 the soil, yet that the increase was never so 

 great as theoretical considerations would lead 

 us to suppose. Thus, estimating a bushel of 

 wheat and its proportion of straw, to contain a 

 pound of nitrogen, it might be supposed that if 

 nitrogen was wanted, a pound of nitrogen, ap- 

 plied in soluble ammonia salt, would give an 

 extra bushel of wheat; but this is not the case. 

 Without making any pretensions to settle the 

 exact amount, Mr. Lawes estimates, from the 

 immense number of instances in whieh ammo- 

 nia has been used, in various ways and propor- 

 tions, in his experiments, that five times as 

 much nitrogen, in the form of am mania, ia re- 

 quired to pro-luce a bushel of wheat, as it con- 

 tains when grown. This estimate has stood 

 the test of many trials, and is in accordance 

 With the well-ascertained effects of Peruvian 

 Luano on wheat. Mr. Lawes founds on this 

 fact some very important practical suggestions, 

 but which we cannot at this time refer to Lie- 

 big takes no notice of this opinion, and refers' 

 to the loss of ammonia in these experiments, 

 as though it had escaped the attention of Mr. 

 Lawes, and as though he were the first to point 

 it oof. . and he proceeds to show that the in- 

 crease "bears no relation whatever" to the 

 ammonia added to the soil. This is proving 

 far too much, even for Liebig's own'theory of 

 the action of ammonia as a solvent; but let 

 that pass. The method Liebig adopt* to get 

 at this result, is as follows: 60 lbs. of ammo- 

 nia, say, give in 1844. an increase on the un- 

 manured plot of 10 bushels. This increase 

 contains only 15 lbs. of ammonia, and there- 

 lore Liebig estimates that u beyond all doubt, 7 * 

 45 lbs. of ammonia are left in the soil for the 

 next crop. In 1845,60 lbs. of ammonia asrain 

 give an increase of 10 bushels; but Liebig 

 adds to this the 45 ibs. which he assumes re- 

 main in the soil from the previous year, making 

 105 lbs. ; and in this way he proceeds, adding 

 the ammonia he supposes to remain in the soil 

 to that applied each year, and from the figures 

 obtained proves that the increase bears no pro- 



