608 
Doctoring Trees. 
did not extract anything except a very minute portion of sulphate of lime 
and potash. 
Silica and siliceous sand .... 72*5 
Alumina ....... 12*8 
Carbonate of lime . . . . . 1 • 
magnesia . . , . l-la 
Per and protoxide of iron , . . . • 5'75 
Sulphate of lime . . . . . 1* 
Potash 4-25 
Soda ....... a trace. 
Humus ....... '75 
Vegetable matter, insoluble in alkalies . . 1*50 
Muriates ....... -47 
100-UO 
At common temperature this clay dried slowly and lost 3 per cent. ; 
a heat below redness dissipated 5 per cent., and a red heat 11 per cent., 
of water. 
It will here be observed that of the upper portion, silica, alumina, 
and iron, make up nearly 92 per cent, of the whole mass ; humus going 
for only 2 per cent. Of the immediate subsoil, the same ingredients, 
namely silex, alumina, and iron, give, in the aggregate, the same pro- 
portional amount; and the humus about 1 per cent, more than in the 
upper portion. 
In the inferior subsoil the three ingredients exist in a proportion 
1 per cent, less than in the two other portions, and the humus becomes 
almost inappreciable. All the three gradations appear to be unusually 
poor; but the ratio of clay to flint is constantly increasing in the de- 
scending series. Still there were alkalies* sufficient, jjerhaps, to keep 
fir-trees alive, and to sustain their growth up to a certain age ; but when 
I took them in hand they had ceased to grow ; they had latterly made 
hardly any shoots, and were evidently within a year or two of extinction. 
They were about three or four feet high, and probably twenty years old. 
That I was right in supposing them to be at death's door is proved by 
this, that the greater part of those surrounding my patients are actually 
dead, and I am about to plant tlie ground over again. 
Experiments on Scotch Fir-Trees with different Manures, 1842. 
No. 1. Watered with nitrate of soda in the proportion of 
lljlbs. to 50 gallons of water, or about 1 lb. to 
the rod. 
Sept. 1842. Shoot 1 inch, foliage thin, and not very 
good colour. 
April 1844. No effect. 
Nos. 2 and 3. Nitrate of soda sown dry in the same proportion as 
No. 1. 
Sept. 1842. Both plants of a good colour and toler- 
ably healthy, with shoots from 2 to 2^ inches long. 
Much better than any around them. 
* The ashfs of Norway fir contain in 100 parts, potash 14'1, soda 20*7. 
