270 
THE COTTAGE GARDENER. 
JULY 13. 
Anderson, of Edinburgh, in 1853. 
1854, p. 95):— 
( Farmers’ Almanac , 
Water . 
10,G8 
Oil . 
11,10 
Albuminous compounds ... 
29,53 
Ash (when burnt) 
7,79 
Other constituents 
40,90 
100,00 
The following are some of those “ other constituents,” 
and the proportions in which they 
are found in the 
Rape-cake:— 
Nitrogen ... 
4,38* 
Phosphates 
3,87 
Phosphoric acid ... 
0,39 - 
Silica ’... 
1,18 
Mr. Shier, Fordyce lecturer on agriculture at Aber¬ 
deen, states, that in the Netherlands it is used to 
strengthen the urine and liquid-manures; and that in 
Scotland lie knew it used with urine with remarkable 
success. The oily constituent of the cake probably 
unites with the excess of ammonia in the urine, and 
renders it more enduring, because not so liable to pass 
off into the air. Mixed with peat, or other slowly-decay¬ 
ing vegetable remains, Rape-cake dust is found to hasten 
their decomposition. 
The only crop that of our own knowledge we can say 
is benefited by Rape-cake dust is the Carrot. The dust, 
mixed with the seed, was sown with it in drills, and 
most signally preserved the roots from the Carrot grub, 
which devastated the neighbouring grounds that year, 
and which had been similarly destructive in our garden 
during previous years. 
As a manure for Onions , we have been much obligod 
by the following from a Lincolnshire clergyman:— 
“ I do not think it is generally known, that Rape- 
cake dust, such as is employed in agricultural purposes, 
may be most benefioially used in the cultivation of 
Onions. A full lialf-peck of the dust to an ounce of 
seed, scattered in the drills at the time of sowing. I 
have tried it for the last three seasons with the greatest 
success. Its effects are, this year, peculiarly_evident— 
as I have a splendid bed of Onions, whilst my neigh¬ 
bours have cither lost the whole crop, or can show only 
a few scattered plants. 
“ The Rape dust would appear to be suitable manure 
for all the Onion tribe, as I last year tried it with Leeks 
after they were planted out. The plants were small and 
siokly. I used about a peck of dust to a bed containing, 
probably, three hundred plants. The effect, in a fort¬ 
night's time, was wonderful; and they attained a large 
size before cold weather set in. The dust is equally 
beneficial with Onions sown to stand the winter.’* 
It is quite evident that the Carrot and Onion crops 
are preserved from the grub by the oily constituents of 
the Rape-cake being obnoxious to that larva. 
Bf.fohe any answer can be returned to the question, Is 
irrigated land unhealthy to man and live stock?—a 
distinction must be made between the application of 
* Bourssingault anil Payen found 4,92 per cent. 
pure, living water, and the use of stagnant water, more 
or less charged with substances just ready to pass into 
a state of putrefactive fermentation, and calculated to 
excite and promote such a state among half-decayed 
vegetable matters on the surface of the ground. Much 
confusion of ideas has arisen from omitting any notice 
of this distinction; and yet the two things are as dif¬ 
ferent as need be. In the first instance, the water acts 
mainly as so much water, by virtue of its own peculiar 
living and life-renewing powers, as we shall presently 
see. In the latter case, its action is, in a great measure, 
subordinate aud ancillary; certain manuring substances 
being conveyed to and diffused over the land by means 
of water, and in a liquid rather than a solid state; 
certain new, putrefactive fermentations being thus set 
going, and a rank, rapid, now vegetation arising from 
the decay of the old. For the present, we will confine 
our observations to the first half of the question; re¬ 
serving the latter and more difficult part of the subject 
for future remark. 
Our apology for troubling our readers with these 
details must be—first, the mysterious connexion between 
cholera and other plagues, and our river - courses; 
secondly, the proposal to irrigate land near to towns 
with the sewage of towns, in connexion with works for 
improving the public health. 
Frequent alternations" of wet and dry weather—sun¬ 
shine and showers combined—are well known to have 
a marked influence on the growth of the grasses, the 
leaves of trees, and every green thing. The difference 
between the yield of hay after a “ droppy” spring, and 
after a dry one, should convince the most sceptical of 
farmers of the value of mere water as a manure. A 
considerable annual amount of rain-fall seems requisite 
even for the profitable cultivation of the large-leaved 
Turnip crop. Wo pity the man for whom it was 
written— 
“A Primrose by a river’s brim, 
A little Primrose was to him— 
A Primrose—nothing more !” 
Believing that a great deal more may be mado of the 
fact, that “on the sides of streams and springs we see 
the margins, which have been from time to time sub¬ 
merged in winter, clothed in the early part of the 
season with verdure. Doubtless, the main effect is due to 
the action of the water itself on plants and the soil. It 
contains atmospheric air, and, usually, carbonic acid. It 
further contains certain saline bodies (with finely, 
divided earthy matters of different kinds, and, in certain 
cases, a considerable proportion of organic substances). 
But the ground must not be too long submerged; and 
the current should pass over plants chiefly in the early 
stages of their growth when vegetation is feeble, or 
inert, as in winter, or the early part of spring. Tho 
water must not cover the surface so long as to eradicate 
the species of plants it is wished to produce; and must 
be maintained in a gentle stream, so as not to favour the 
growth of plants which grow in stagnant water, or in 
soil surcharged with moisture.”* 
* Mr. Low, whom we have largely quoted above, admits the difficulty 
of exactly accounting for the modus operandi of water In this ca.e. 
This handmaid of nature is a very different sort of character when idle, 
