HORTICULTURAL JOURNAL. 143 



Translated from the Comtes Rendus. 



INFLUENCE OF AMMONIA ADDED TO AIR UPON THE 

 DEVELOPMENT OF PLANTS.* 



BY M. VILLE. 



On adding ammonia to the air we find the activity of vegetation to be 

 much increased. In the proportion 4,10,000 of the whole air this effect 

 shows itself at the end of eight or ten days, and from this time its intensity 

 steadily augments. The leaves, at first of a pale green, assume a shade 

 more and more deep, until they become nearly black. Their foot-stalks 

 grow long and straight, and their surfaces large and glossy. At last, when 

 the growth has reached its maturity, we find that the product is much larger 

 than that of the same plants grown in the pure air. This product is at the 

 same time heavier and contains more than double the amount of nitrogen. 



Thus ammonia added to air produces two effects on vegetation — first, it 

 favors the growth of plants ; and second, it renders them more nitrogenous. 

 Thus in an experiment made in 1850, the product in pure air was 64.19 

 grammes, and that in the air containing ammonia was 110.06 gr. The first 

 contained 1.266 gr. of nitrogen and the second 4.313 gr. 



In 1851 the product in pure air was 68.72 gr. and contained 0.494 gr. of 

 nitrogen. In the ammoniacal air the product was 135.20 gr. and contained 

 1.501 gr. of nitrogen. 



Besides these general effects produced by ammonia, there are others of a 

 more variable nature dependent on special conditions, but which are not less 

 interesting. Indeed, by means of this gas we are able, not only to increase 

 the activity of vegetation, but even to modify its progress, to weaken the 

 exercise of certain functions, and to increase, without limit, the development 

 or multiplication of certain organs. 



If we expose the plant to the action of the ammonia some months before 

 the time of flowering, its growth is more rapid, but is not accompanied by 

 any disturbance of the usual succession of phases in its growth. It often 

 happens indeed that plants, which when cultivated in pure air fail even to 

 produce flowers, when grown in ammoniacal air produce matured fruit. But 

 if we change the conditions of the experiment, if we wait until the plant is 

 on the point of flowering before submitting it to the action of ammonia, the 

 results are entirely different, the stem shoots up and sends out branches in 

 every direction, clothes itself with innumerable leaves, and, if the season is 



* In our last volume we extracted a condensed account of M. Ville's ex- 

 periments ; we have been favored by one of our lady readers with a transla- 

 tion of the original article. 



