10 
CAROLINE RUMBOLD 
records of this year. The records of the previous and succeeding years 
confirm the 1913 figures. 
Rate of Absorption of Injected Substances 
This compilation was made from the records of the injections made 
in 156 Paragon chestnut trees during the growing season of 191 3 and of the 
weather during that period. 
The therapeutic bias of the work decidedly limited the scope of the 
experimental injections, and in consequence data are wanting for a complete 
record of the rates of intake. The effort was to find the dilution at which 
a substance entered a tree readily without killing it. When a tree showed 
injurious efi^ects of an injection, the injection stopped whether it had been 
going for two days or for a week. 
It was the policy in 1913 to inject large quantities of dilute solutions, 
on the supposition that the dilution decreased the toxicity of the substance 
near the point of injection. At the same time the tendency of the lignified 
cell walls to retain the substance was relied on to dilute the solution still 
further in its passage toward the leaves, so that the latter would not ac- 
cumulate so much before autumn as to cause them to die. In consequence 
of this effort the data on the rate of absorption are very incomplete. 
Table i . Substances, with Their Dilution, Injected Into Trees 
No. of trees Substance No. of trees Substance 
Ammonium: 
4 (NH)2C03 i/ioo G.M. 3 Acetic acid 
4 (NH4)0H I /i 00 approximately (2) i/iooo G.M. 
6 (NH4)2S04 (i) 1/3000 
(1) i/ioo, changed later to 1/50 3 Benzoic acid 
(2) i/ioo (i) i/iooo 
(2) 1/200 (2) 1/5000 
(1) 1/500 3 Citric acid 
2 NH4CI 1/200 (i) 1/500 
Sodium: (i) 1/3000 
7 NaaCOs (i) 1/5000 
(4) i/ioo 3 Formic acid 
(2) 1/200 (i) i/iooo 
(i) 1/500 (2) 1/6000 
4 NaCl 3 Lactic acid 
(3) i/ioo, changed to 1/50 (2) i/iooo 
(i) 1/200, changed to 1/50 (i) 1/2000 
7 NaOH i/ioo G.M. 4 Picric acid 
Lithium: (i) 1/500 G.M. 
5 LiOH (i) i/iooo 
(i) 1/200 (2) i/ioooo 
(3) 1/500 2 Pyrogallic acid 
(i) i/iooo (i) i/ioo 
5 LiaC (i) i/iooo 
(i) 1/200 3 Salicylic acid 
