THE FARMER'S MAGAZINE. 



157 



eertaialy iuvestigate as soon as circumstances wiil 

 admit, the strong proportion of nitrogen found in the 

 Helianthuses would have two causes : a part would 

 come from the albuminous matter, the other from 

 ammoniacal salts. I will add that it is not indispensa- 

 ble that plants be manured with ammonia, exclusive of 

 any other alkali, that they may contain ammoniacal 

 salts ; it is sufficient that they grow in land strongly 

 manured with stable dung : and I apprehend that crops 

 stimulated with fermented human dejections, in which 

 carbonate of ammonia is dominant, must contain a very 

 notable proportion. I have repeated upon hemp plants 

 the experiments made upon Helianthuses. 



Fourth Experiment. — Vegetation of Hemp 

 Plants, in the open air, in a soil, destitute of Organic 

 Matter, and containing Phosphate of Lime and 

 Vegetable Ashes. 



Doses of nitrogen in hemp seeds. 



Gr. Nitrogen. Per-eentage. 



In 7 seeds, weighing . . 2-8675. . Oi 05555.. .. 3-721 



la 42 seeds, weighing . . 14'3220. . 2-055915. . . . 3 712 



Seven seeds, weighing 2.8675 gr., were sown into 

 white granulated calcined sand, contained in a flower- 

 pot equally calcined, and manured with 30.10 gr. of 

 phosphate of lime, and 4.65 gr. of vegetable ashes.' 



On the thirteenth dag the cotyledtms had lost their 

 colour ; the highest stem was not more than 1 inch and 

 three-sixteenths in heiglit ; the first leaves were deve- 

 loped. 



On the fiftieth day the male plants, 5| inches high, 

 had each preserved four leaves ; the inferior leaves were 

 withered. The female plants were only 1^ inches high. 

 All were covered with flowers ; upon one of them four 

 small but well-formed seeds were found. 



These seven limit plants weighed, on being dried up, 

 4.7275 gr. — not quite double the weight of the seeds 

 planted. 



Nitrogen. 

 grains. 



In the seven plants was found 0.063395 



The sand weighed 4877.850 gr. 



The flower-pot 3360.400 gr. 



8238.25 gr. 



Nitrogen 

 found. 



The fourth 2059.64 gr. 0.025265 gr. 



The tenth 823.82 gr. 0.010230 gr. 



In 2883.46 gr. 0.035495 gr. 



In the total 8238.25 gr 



0.101370 



luthecrop 0.164765 



lu the seeds 0.106795 



Gain in nitrogen after 50 days' vegetation 0.057970 



Each limit hemp plant had, then, acquired in fifty 

 days' vegetation 0.00775 gr. of nitrogen, equivalent to 

 0.0465 of albumen ; and, from the amount of vegetable 

 matter elaborated, this plant, the weight of which did 

 not exceed 0.682 gr., must have decomposed on an ave- 

 rage, and per day, 0.918 cubic eighths of an inch of car- 

 bonic acid gas. The dried up limit plant contained 

 1.23 per cent, of nitrogen ; and it is very remarkable 

 that, as I found it in a hemp plant taken from a field, 

 there should be in a full-grown plant nearly the same 

 proportion of nitrogen, viz., 1.52 per cent. 



Fifth Experimp:nt. — Vegetation of Hemp in the 

 open air, in a soil destitute of Organic Matters, con- 

 taining Phosphate of Lime, Vegetable Ashes, and, as a 

 nitrogenous manure, some Nitrate of Potash. 



The soil, formed of white and granulated quartz saad. 



had been washed and calcined. The fiower-pot weighed 

 3332.5 gr. With the sand were mixed the following 

 substances : — 



I'liosphate of lime . l.SO gr. 



A't'getable ashes 3.10 



Nitrate of potash 10.85 



After having watered with pure v/ater the sand, which 

 weighed 10850 gr., five hemp seeds were sown, weighing 

 2.040 gr., and in which there must have been 0.0G795 gr. 

 of nitrogen. 



On the forty-third day the highest stem (male) was 

 about 12 inches high, the shortest (female) 7.\ inches. 

 The five plants bore flowers ; upon one of ihem green 

 seeds were seen. 



After being dried-up, the plants weighed — 



Leaves and blossoms.. .. , 11.8575 gr. 



Stems 7.3625 



Roots 9.7650 



28.9850 



From an analysis made of half the crop, I came to the 

 conclusion that — 



Nitrogen, 

 grains. 



The whole 28.9850 gr. contained 1.67450 



There was found in the soil 6.394525 gr. nitrate, 



equal to 0.88505 



Nitrogen found 1.55955 



The soil had received^lO.85 gr. nitrate, 



equal to nitrogen 1.50164 gr. 



The seeds contained 0.07595 



1.57759 



Difference 0.01804 



It is seen from the above table that the nitrogen 

 brought by the nitrate was found again, both in the 

 plants and in the soil. 



Under the influence of a manure containing soluble 

 nitrogen, such as saltpetre, the assimilation of carbon 

 was much more apparent than when the plants were 

 supplied with phosphate of lime only. In one month 

 and a-half the five hemp plants had elaborated 20.939 gr. 

 of vegetable matter, in which there were 10.7725 gr. of 

 carbon; so that, on an average, and per diem, 11.85 

 cubic inches of carbonic-acid gas had been decomposed. 



To complete the programme which I had drawn for 

 myself, there still remained to examine what would be 

 the development of hemp plants having for manure a 

 nitrogenous matter alone, without the concourse of 

 phosphate of lime. 



Sixth Experiment. — Vegetation of Hemp in the 

 open air, in a soil containing only Carbonate of Am- 

 monia. 



Seven hemp seeds, weighing 2.8675 gr., were sown 

 into 10850 gr. of calcined quartz sand. After the ap- 

 pearance of the cotyledons, the plants received known 

 quantities of carbonate of ammonia in solution, which 

 were applied every time the soil was watered. 



On the twenty-fifth day the tallest of the stems was 

 2 1 inches high ; the cotyledons were withered. 



On the thirty-seventh day the tallest stem was 5J 

 inches high ; the blooming was very forward. 



On the forty-ninth day seeds were formed; the tallest 

 stem was 5-2 inches high; the shortest about 4 inches. 



The plants, after being dried-up, weighed 11.8576 gr. 

 — a little more than four times the weight of the seeds. 



There was found in the crop — nitrogen, 0.35805 gr. 



In the course of the experiment there had been 

 poured into the soil 563.80 cubic eighths of an inch of 

 a solution of carbonate of ammonia, containing 19.53gr. 

 of alkali, or 16.12 gr. of soluble nitrogen. 



Thus, under the action of a nitrogenous manure, and 



