408 



THE SOUTHERN PLANTER. 



From the Country Gentleman., 



How do the titrates of Soda and Potash 

 produce their Fertilizing Effects. 



The agricultural public has had several op- 

 portunities, during the last two or three years, 

 of becoming acquainted with the very remark- 

 able effects which the nitrates above-named 

 usually produce upon vegetation generally, and 

 more especially upon the growth of various 

 grass and grain crops. So frequently have the 

 nitrates, and especially the nitrate of soda, 

 been used as fertilizers in the way of top dres- 

 sings and otherwise, and so uniformly have 

 very notable effects been produced, that it may 

 be considered as a well established fact that the 

 nitrates of soda and potash contribute very ma- 

 terially to the luxuriance of vegetation in sev- 

 eral classes of plants, among which grasses 

 and cereals stand pre-eminent. 



When a fact of this kind becomes well estab- 

 lished, there are always minds whose propen- 

 sities to investigate and philosophize lead them 

 to endeavor to discover the mode in which the 

 cause operates so as to produce the effects. 

 Some have this propensity to investigate and 

 discover the manner or steps in the process by 

 which remarkable results are produced, so very 

 strong, that they can give themselves no rest 

 until this modus operandi, or mode of opera- 

 tion as it is called, has been satisfactorily de- 

 termined. This propensity to investigate into 

 causes, modes of operation, and to seek expla- 

 nations as to the how and the why of impor- 

 tant events, has been implanted in our mental 

 constitution for wise and good purposes ; and 

 has often led to the discovery of first princi- 

 ples of the utmost importance. 



Urged on by this intellectual curiosity, and 

 by the hope of some fortunate discovery of a 

 valuable principle or first truth in agriculture, 

 a French chemist " not unknown to fame/' M. 

 Boussingault, has of late been making some 

 experiments on the modus operandi of the ni- 

 trates of soda and potash, when they act as 

 fertilizers or promoters of a luxuriant vegeta- 

 tion. The results of these experiments M. 

 Boussingault has lately communicated to the 

 Academy of Sciences in Paris, in full detail. 

 This full detail of M. B.'s experiments and re- 

 sults would prove tedious and uninteresting to 

 the bulk of our readers ; but a highly abridged 

 summary thereof may prove of interest and 

 value, we trust, to not a few. With such a 

 hope, we have endeavored to condense the 

 more interesting and instructive portions of M. 

 Boussingault' s paper into the few paragraphs 

 which follow. He wished to determine how 

 far their efficacy was owing to the alkalis which 

 formed the base of these salts, all alkalis hav- 

 ing some effect upon vegetation, and how far 

 it was owing to the nitric acid with which the 

 alkaline base was in combination. 



The only explanation of the useful effects of 

 the nitrates on vegetation of which M. B. had 



any knowledge before commencing his experi' 

 ment, was that of M. Kuhlman. That skilful 

 chemist has arrived at the conclusion, that 

 when the nitrates act as fertilizers, their nitro- 

 gen, before being absorbed by the plant, is 

 transformed most frequently into ammonia in 

 the soil itself. To obtain the full value of the 

 nitrates, according to this theory, these salts 

 must be placed "under the deoxidating influ- 

 ence of a putrid fermentation, of which the 

 definite result will be the carbonate of ammo- 

 nia." In regard to this theory, M. Bousingault 

 remarks that it is to be regretted that M. Kuhl- 

 man has not investigated whether organic 

 matters in the progress of putrefaction do re- 

 ally convert the nitric acid of the nitrates into 

 ammonia. M. B. on this account, thought it 

 proper to examine if the presence of putrefy- 

 ing organic matters in the soil is indispensable 

 for the nitrogen of the nitrates being assimila- 

 ted by the plant, for if it should appear that 

 assimilation takes place in their absence, we 

 would be at liberty, as M. B. remarks to draw * 

 two conclusions: 1st. That it is not necessary 

 that the nitrogen of the nitric acid be previ- 

 ously converted into ammonia in the soil before 

 becoming fit to, be assimilated by the plant ; 

 and 2nd. That in their effects on vegetation the 

 nitrates do not act solely as salts by means of 

 the base of potash or of soda. 



The process which M. Boussingault adopted 

 consisted in making a plant grow in sand which 

 had been rendered quite sterile by calcination, 

 adding to it a known quantity of an alkaline 

 nitrate and ashes. The watering was done 

 with pure water ; and after the plant was fully 

 developed, it was analyzed to ascertain the 

 quantity of nitrate it had absorbed, while the 

 amount of nitrate remaining in the soil was 

 also determined. 



In the first experiment, two seeds of the sun- 

 flower, weighing together 0.062 grammes,* 

 were deposited on the 10th of May, 1855, in 

 calcined sand, with which had been mixed 0.1 

 gr. of alkaline ashes, and 1.0 gr. of washed 

 ashes, and successively in the course of the ex- 

 periment 1.11 gr. of the nitrate of potash. The 

 sand was moistened at the commencement with 

 pure water, and after germination with water 

 saturated with carbonic acid. The plant grew 

 in the open air, under a glass roof, which shel- 

 tered it from the rain and the dew. On the 

 19th of August one of the plants had obtained 

 the height of 0.72 metres, f and carried nine 

 fresh leaves and one floral bud, with some faded 

 leaves at the lower part of the stem. The 

 other sunflower was 0.50 metres in height 

 (about 18 inches,) and had six fresh leaves of a 

 beautiful green, and seven faded ones. The 

 two plants after being dried, weighed 6.685 



* French gramme is equal to 15.4325 grains 

 troy. 



f A metre is equal to 3.286 feet. 



