486 MR. J. B. LAWES, DR. GILBERT, AND DR. PUGH ON 
The investigations of ScnéyBErn and others appear to show that, under certain cir- 
cumstances, nitric acid may be formed by the mutual action of Ozone and free Nitrogen. 
The question for our consideration here is, whether these circumstances are presented 
in the cells of plants, and in the passages between them, during growth? The subject of 
the relation of Ozone to organic matter is obviously too extensive for anything more 
than a passing consideration here; but we may refer to the well-known intense action 
of this peculiar body upon organic matter generally, by which carbonic acid is formed, 
and the Ozone destroyed. It is well known that Ozone is rapidly destroyed if kept in 
contact with phosphorus or any other reducing substance. If such conditions for the 
destruction of Ozone exist within the plant, the probability that it can there oxidate free 
Nitrogen, and so form nitrates, would appear to be exceedingly small. The actual con- 
ditions within the plant in regard to the points in question may be most efficiently 
studied by the examination of the gases they contain, under various circumstances. We 
proceed, therefore, to notice some of the results of such an examination. 
B.— Composition of the Gas in Plants. 
Experiments, Series 1. 
Plants, or parts of plants, were put into a flask filled with water that had previously 
been well boiled to remove all air from it. A cork, through which a bent glass tube was 
passed, was then pressed into the flask, so that the tube was filled with the displaced 
water. The flask was then placed over a lamp, the water boiled, and the water and gas 
driven over collected over mercury, the boiling being continued until the water distilled 
over raised that first driven out with the gas to the boiling-point. The vapour thus 
produced expelled most of the water collected over the mercury. In this way the gas 
driven out from the plant at the boiling-point was obtained. The following Table (I.) 
shows the composition of the gas collected under these circumstances. It is seen that 
Nitrogen and Carbonic acid only were present. 
TasLe I.—Showing the Percentage Composition of the Gas evolved from plants, 
in water, on continued boiling. 
Description of plant operated upon. Per cent. 
Date 
(1857). Plant. | Part of plant. How manured, &. Nitrogen. | Oxygen. ee 
May 6. | Wheat. | Whole plant. |Mineral manure ..........ssseeeeeeseeseeeel| 45°47 0-0 54°53 
May 2. | Wheat. | Whole plant. |Mineral manure ..........ccsecseeseseeseee|]| 46°29 0:0 53-71 
May 2. | Wheat. | Lower part. |Mineral manure ..........cecseccseeeeeeeee]] 57°00 0-0 43:00 
May 2. | Wheat. | Whole plant. |Mineral and Ammoniacal manure...... 39°14 0-0 60°86 
May 2. | Wheat. | Upper part. {Mineral and Ammoniacal manure...... 37°53 0-0 62°47 
May 6. | Bean. | Whole plant. |Mineral manure .........cccsesesceseesevee|] 62°79 0:0 37°21 
May 6. | Bean. | Whole plant. |Mineral manure .............csccceeeeeeees|| 63°80 0:0 36°20 
Other experiments gave similar results, all tending to show that the reducing power 
