542 
ME. J. B. LAWES, DE. GILBEET, AKD DE. PUGH ON 
Appendix. 
Eeceived subsequently to the reading of the paper. 
A. — Preparation of solutions for manuring the Plants, dates of application, 
and quantities applied. 
Sulphate-of-Ammonia solution. — Ordinary ammonia-water was distilled from a flask, 
the vapour condensed in a receiver containing pure distilled water, and the strength of 
the solution determined by the volumetric method, by means of dilute sulphuric acid of 
known strength, the preparation of which is described further on, at p. 545. A given 
volume of the ammoniacal liquid thus prepared was neutralized by pure dilute sulphiuic 
acid, of which the quantity added was determined by measurement, and the strength of 
the solution calculated accordingly. It was intended that each cubic centimetre should 
supply about one-tenth of a milligramme of combined nitrogen. The exact strength of 
the sulphate-of-ammonia solutions used in the course of the experiments was as under : — 
Table I. 
When used. 
Volume of the pipette 
measure employed. 
Combined nitrogen in a 
pipette measure of the 
solution. 
In the experiments of 1857 
septems*. 
gramme. 
111-2 
0-00578 
In the experiments of 1858, to August 10 inclusive 
1000 
0-004 
In the experiments of 1858, after August 10 
100-0 
0-00359 
Tables II. and III. show the dates of the application of the above solutions to the 
difierent plants, and the amounts of nitrogen so supplied. 
Table II. — Showing the supply of combined Nitrogen, as Sulphate-of-Ammonia solution, 
to plants grown in 1857. 
Dates. 
Nitrogen supplied. 
Wheat, in pre- 
pared soil. 
Wheat, in pre- 
pared pumice. 
Barley, in pre- 
pared soil. 
Barle.y, in pre- 
pared pumice. 
June 10 
July 4 
July 11 
July 22 
July 29 
gramme. 
-00578 
-00578 
•00578 
•00578 
•00578 
gramme. 
•00578 
•00578 
•00578 
•00578 
•00578 
gramme. 
•00578 
•00578 
•00578 
•00578 
•00578 
gramme. 
•00578 
•00578 
•00578 
•00578 
Total 
•02890 
•02890 
•02890 
•02312 
* A septem measure is that of 7 grains (=xoVo of a pound avoirdupois) of vater ; that is, rather less 
than half a cubic centimetre, which is equal to 15‘43235 grains (or 1 gramme) of water. 
