REPORT OF THE CHEMIST. 55 



aREENSAND MARL. 



A sample of greensaud marl from the lands of G<'orpre B. Westcott, 

 near Caulks's Field, Kent Conuty, Maryland, was submitted for analysis 

 by Paymoster Frank C.Cosby, United States Kavy, and was found upon 

 analysis to contain — 



Per cent. 



Sand and silica 63. 96 



Potaesa 4.4 



Piiosphoiic acid 0. 33 



showing it to be very inferior in quality to similar material from the 

 deposits in New Jersey, in which the potassa ranges from 3 to 10 per 

 cent, and the phosphoric acid from to C per cent. 



In addition to the results of our own investigations, I consider it of 

 value to introduce here a brief synopsis of the facts relating to agricult- 

 ure and agricultural chemistry that have been developed during the 

 past year by investigations made in Europe, as the work has been 

 attended with results of the highest interest and importance In a prac- 

 tical as well as a scientific point of view. 



The investigations into the questions of mineral nutrition of plants 

 during the past year have mostly been with particular reference to 

 culture of the beet ; but Boehm has made experiments upon the influ- 

 ence of lime salts upon vegetation in general, from the results of which 

 it appears that these compounds are necessary concomitants of the pot- 

 ash salts in the formation of starch and allied products in the vegetable 

 organism. The opinion has been general that the function of potash 

 was directed especially to this end, but the experiments in question 

 have shown that when not associated with lime, or its in absence, they 

 may have an absolutely poisonous influence. Boehm is therefore of 

 the opinion that lime salts are as essential to the formation of starch, 

 and to the change of starch to sugar, &c., in building up the cell-walls 

 which constitute the skeleton of the plant as it is in the animal economy 

 in the metamorphosis of the cartilage of the bones. The notion thus 

 advanced, that the function of potash in the promotion of the formation 

 of sugar in plants is limited, has received confirmation in the results of 

 the investigations of Joulie upon the relation of the elements of fertil- 

 izers to the composition of beets, which show that the richness in sugar 

 is favorably affected by phosphoric acid, but is not increased by the 

 alkalies or nitrogen compounds. These latter elements, if applied in 

 moderate quantities, may serve to augment the yield of beets ; but if 

 they exist in the soil in excess of the amount required by the crop in nor- 

 mal physiological development, they become injurious to the quality 

 — the alkalies by increasing the saline constituents, and the nitro- 

 genous compounds by increasing the size of the beet and reducing 

 the saccharine constituents. These results agree closely with those 

 of Fremy and Deherain, who have found that the richness in sugar is 

 not affected by different characters of the soil, such as argillaceous, sili- 

 ceous, or calcareous; that calcic phosphate and potassic nitrate in sterile 

 soils have a favorable effect on the quantity of the product and its 

 richness in sugar, and that excess of nitrogenous manures is injuri- 

 ous. With reference to the nitrogen compounds, Joulie finds that 

 the nitogen of nitric acid is preferable in this connection to that of 

 ammonia, which, in its turn, is more valuable than organic nitrogen. 

 When used in the form of nitrate, the soda compound may replace with 

 advantage the potash compound, and at the same time bring about a 

 reduction of the total alkalies in the products. Stable manures should 



