460 MR. J. B. LAWKS, in;. r;ii.i;i:i;T. Wit m;. itch 01 



From the result of the whole inquiry, the Commission announced the following con 



elusion : — 



That the (,ijn rinn ni imiilr at the Mn: in 111 OFHistoire WatwreUe "by M. Ville, is <?<>«<- 

 sistent with the conclusions which he has drawn from Ms />revious labom , 



8. M. G. Villb's experiments in which the plants were exposed to free air, and "Nitrate* or 



Ammonia salts mere employed, as manure*. 



In 1855 and 1850, M. G. Ville conducted a scries of experiments with the double 

 object, of investigating the action of nitrates upon vegetation, and of still further 

 examining into the capability of plants to assimilate the free or oncomhined Nitrogen 

 of the atmosphere. The whole of the experiments now in question were made in free 

 air, the plants being only shaded from rain; that is to say, without any enclosing appa- 

 ratus, or artificial current of air and supply of carbonic acid. The soils consisted of 

 calcined sand; ashes of plants such as those to be grown were added; and distilled 

 water was used for watering. Colza and Wheat were the plants experimented upon. 

 Lastly, the special conditions of the experiments were, that nitrate of potash in smaller 

 or in larger quantity, or nitrate of potash and different ammonia salts, in equivalent 

 quantities so far as their Nitrogen was concerned, were employed. 



To the prosecution of this series of experiments, an exact method of estimating minute 

 quantities of nitric acid was essential. M. Ville succeeded in devising such a method, 

 which was very favourably reported upon by M. Pelouze, on behalf of a Commission 

 composed of MM. Balaed, Peligot, and Pelouzk. 



In 1855, two pots, and in 1856 one pot, of Colzas were grown, to each of which 

 05 gramme of nitrate of potash was supplied as manure. By examination of the soil, 

 the point was ascertained when the whole of the nitrate had been drawn from it by the 

 plants. The experiment was then stopped ; and analysis showed that the total produce 

 contained almost identically the amount of Nitrogen supplied in the seed and in the 

 nitrate. The dry vegetable substance was, however, increased about 200-fold. 



Again in 1855, two pots of Colzas were sown, to each of which 1 gramme instead of 

 - 5 gramme of nitrate was added ; and in 1856 two more, with the same quantity. 

 In each of these cases, the produce (which in dry matter was several hundred times that 

 of the seed) contained considerably more nitrogen than had been supplied in the seed 

 and in the nitrate. M. G. Ville 's conclusions were, that the plants had taken up the 

 nitrate and assimilated its Nitrogen, and that when by the larger supply of nitrate the 

 growth had been extended, the free Nitrogen of the atmosphere was also assimUated. 



In 1855 an experiment was made with Wheat manured with 1-72 gramme of nitrate 

 of potash. The plants were allowed to mature, and they gave 84 grains. There was 

 more Nitrogen in the vegetable produce alone, than in the seed and nitrate, and very 

 much more in the total products, taking into account the residual Nitrogen in the soil. 

 In 1856, two pots of Wheat were sown, to each of which 1*765 gramme of nitrate were 

 added. The plants of one pot were taken up at the time of flowering, and they contained 

 * Becherclies Exp&iinentales sur la Vegetation, 1S57. 



