68 
JOURNAL OF HORTICULTURE AND COTTAGE GARDENER. 
[ July S6,18£3. 
about 10 per cent. ; and in one case actually superior crops resulted. 
In the case of the soluble phosphates the quantity given was equal to 
100 lbs. of phosphoric anhydride per aero, in the case of the insoluble 
150 lbs. were given ; those quantities costing about the same sum. 
Thus, while the crops in the first instance were nearly equal, the 
phosphate remaining in the soil would be much greater in the case of 
the insoluble than the soluble, and would affect the after crop to a 
much greater extent. Indeed, this was found to be the case. Not 
only so, it was found that the Turnips were much more prone to 
disease after dissolved than undissolved phosphates. It appears that 
the fungus which causes the disease feeds more particularly on the 
pungent oil found in Turnips and other members of the order ; that 
this oil is rich in sulphur, and that the sulphuric acid present in 
dissolved phosphates favour the disease by promoting the production 
of the oil in question. Whether this theory be correct or not, there can 
be no doubt as to the facts ; and as the Bra^sica order have to follow 
each other in closer rotation in the gardens than in the field, the 
danger will be the greater ; for it is found that when Cabbages or 
Turnips follow in too rapid succession finger-and-toe, clubroot, and 
other diseases often decimate, if not totally ruin, the crop. But when 
bones, fowl or pigeon manure, and human excreta are used to supply 
the phosphates demanded, superphosphates will hardly be wanted. 
Space here does not permit, otherwise we would refer at length to the 
experiments with soluble v. insoluble phosphates in Sussex ; but the 
conclusion arrived at after elaborate experiments under a variety of 
experiments was, that a mixture of bone flour and ground copjrolite 
was the most economical manure to use so far as phosphates were 
concerned. Owing to the greater solvent power of garden soil they 
will, doubtless, prove even superior in the garden to what they have 
in the field. 
As the manufacturers of superphosphate derive most of their profit, 
not from the phosphates, but the vitriol necessary for their reduction, 
and as those who make their own superphosphate at home must at 
least buy this, it does not pay to make it at home where the appliances 
are necessarily rude. Still, many people like to make their own, and 
especially those who have collected a quantity of bones. For those 
who are anxious to reduce these we may describe an easy inexpensive 
method of doing so. A large wooden trough or tub in which to mix 
the materials, and a wooden spade is necessary. Iron tools are worse 
than useless. A coating of pitch will be an improvement, as it will 
preserve the tub from being charred by the acid. Even this may be 
dispensed with, as the process may be conducted on the bare ground 
if a close firm spot is chosen into which the acid will not scak. To 
prevent the liquids running away a rim of ashes will be necessary. 
The finer the bones are broken, cr the mineral phosphates ground, the 
more rapidly will the transformation take place. In ( the operation 
three things are necessary—phosphate, acid, and water. There are 
many kinds of phosphates, as Ave have pointed out, and an extra 
alloAvance must be made for those Avhich contain a considerable 
amount of calcic carbonate, ferric oxide, alumina, &c. There 
are three kinds of acids—white, broAvn, and chamber : 64 lbs. of 
white (specific gravity 1-845°), 82 lbs. of broAvn (specific gravity 
1-700°), and 114 lbs. of chamber acid (specific gravity 1-450°) are 
the quantities required to convert 100 lbs. of insoluble phosphate into 
soluble. Brown acid is usually used because it is considerably less 
expensive than the purer white. Except Avhen it is manufactured 
chamber acid is seldom used, the cost of the carriage of mere water 
making it less economical than brown, Avhich is cheapest, unless when 
the distance from the manufactory is great, Avhen the white may be 
rs?d. The amount of Avater employed is about 3 in 40. Half of this 
is commonly used for thoroughly moistening the phosphates and half 
for diluting the acid. Afteiwards the acid is poured on the bones, &c., 
and the Avhole thoroughly mixed. When mineral phosphates are used 
it is Avell to have more acid than enough rather than less, and to add 
bone dust afterwards. By so doing most of the phosphate will be 
dissoHed, which is not usually the case. The addition of bones after¬ 
wards will reduce the amount of soluble matter, yet not the value of 
the compound, but the reverse. 
At a manufactory in our neighbourhood the folloAving rule is 
observed in the manufacture of a mineral superphosphate guaranteed 
to have from 25 to 28 per cent, of soluble phosphate (this term 
usually misleads ; soluble phosphate is not meant, but tricalcic 
phosphate rendered soluble, Avhich is cf course very different) :—One 
ton of Cambridge coprolite, 17 cwts. of broAvn acid, and 3 of water. 
For “ dissolved bones ” 7 cwts. of half-inch bones, 13 of coprolite, 
16 of brown acid, 3 of water, and (aftenvards for drying) 2 of plaster 
of Paris. This gives about 244 per cent, of soluble phosphate as Avell 
as fully 1 per cent, of (nitrogen equal to) ammonia. Other pro¬ 
portions are used, b t these Avill sufficiently indicate to the beginner 
the proportions of the different materials wanted. 
Soluble phosphates soak into the soil and so are thoroughly distri¬ 
buted. When precipitated by lime they are readily used ; Avhen, as on 
rusty ground deficient in 1 me, iron oxide precipitate them they are 
not considered so available ; but it is considered that the iron 
ultimately takes the place OA’er of the lime. In such cases it may be 
Avell to precipitate them beforehand, otherwise lime in any form, 
except the sulphate, should not be used for drying or diluting the 
newly made superphosphate. Bone dust is best, but ashes, sand, 
or dust Avill suit. The better they are dried and the more finely 
pulverised the more easily are they distributed A\-ith uniformity. 
While for long bones have been used in the construction of ine 
and other bordeis and for trees and plants in pots, it is to be 
regretted that anything like scientific experiments Avith phosphates in 
the garden as in the field are unknown. We may reason from 
analogy ; Ave may point out that garden crops demand phosphates 
largely, and that garden manures supply them sparingly ; Ave may 
instance numberless cases where bones and other forms of phosphates 
have been used, and success has attended ; but, compared Avith Avhat 
has been done for agriculture, we gardeners have not yet made a 
beginning. Indeed, but for the rays reflected from, agricultural 
chemistry, garden chemistry would still be obscured in darkness. 
What Ave know of the solvent power of soils, and the facility with 
AA-hich roots in general attack other mineral substances, we can hardly 
be wrong in supposing that a libei-al addition of ground or even 
broken coprolites to borders, Avhich are “ made to last a lifetime,’ 
would proA-e a lasting and satisfactory source of the phosphoric 
anhydride Vines, Peaches, and other fruits need. We can hardly 
doubt but many an acre of orchard soil could thus be cheaply 
improved ; but nobody has proved it, and Ave want proof, without 
AA T hich Ave must found our hopes of success on what is likely rather 
than on Avhat is certain. 
Phosphates can hardly be applied Avrongly to A T ery old soils,.or 
indeed any, for the reasons already given. All garden crops require 
them. Old worn-out laAvns greatly benefit from such, especially AA T hen 
applied a year after a dressing of lime has been given to kill moss 
and sweeten the under soil. Grasses, and especially the finer kinds, 
depend for their A-ery existence on finding phosphates ; Avhen these 
fail in the soil other plants that do not so much depend on phosphoric 
anhydride usurp their place. In cases of extreme poverty an addi¬ 
tion of some nitrogenous manure will help the action of the other ; 
but finely ground bones, preferably steamed bone flour,, is perhaps 
the best either for encouraging fine grasses on inferior soils or 
renovating these on old turf. From 5 to 8 cwts. per acre may be 
regarded as a good dressing ; for kitchen garden or flower ground 
from 5 to 10 CAvts. suffice for CaulifloAvers or Cabbages, 2 or 3 cwts, 
for Potatoes, but none Avhen these folloAv Cabbages Avhich have been 
liberally dressed the year before. 
As illustrating the effect of carbonic dioxide on the solubility of 
different phosphates, and as a guide to the solvent poAver of the soil, 
Ave may add that Mr. C. P. Williams found that the folloAving, Avhen 
suspended in water through Avhich the gas Avas passed, became soluble 
in the degrees indicated below :— 
Calcic phosphate in apatite is soluble in... 
„ „ ,, finely ground apatite 
,, „ ,, bone ash . 
„ „ „ burnt bones. 
„ „ „ South Carolina phosphate. 4-122 
„ ,, same finely poAvdered. C'554 
„ ,, in phosphatic guano from Orchilla ... 8’009 
From this it Avill be seen that some phosphates are \ T ery much 
more soluble in the soil than others. Apatite Ave may mention is 
the form knoAvn by the name of Canadian and Nonvegian phosphates. 
—SlXGLE-IIANDED. 
(To be continued). 
Parts oE water. 
999.990 
" 140-840 
6-G78 
8-020 
A STRAWBERRY ENEMY—BIRDS. 
Mr. Robert Grindrod in blaming mice for biting Grape berries 
clean off the bunch (see page 50), gives these mischievous little animals 
a character they do not deserve. Voles and common rats do so, but mice 
content themselves with eating a little out of each berry. The garden 
here is so placed as to bring us a perfect scourge of animals ; rats, mice, 
squirrels, hedgehogs, pheasants, partridges, blackbirds, and sparrows 
congregate together round it as to a common centre, and make them¬ 
selves at home as much as they can. Rats take to fruit very readily. 
Not only are Grapes eaten, but I have occasionally had to Avatch the 
Pear trees and shoot the rats when eating the fruit. Beans they prefer 
to Peas, and when hard pressed for food will eat growing Potatoes. 
Mice like Peas better than Beans, and will destroy the produce in the 
pods as well as when lying as seed in the ground. I do not think mice 
are so fond of fruit as rats are, they seem to prefer grains and seeds. 
Last fruit season squirrels Avere very bad ; very unwillingly they were 
shot down, sometimes as many as five or six in a day. Plums are 
apparently their favourite fruit. 
Pheasants are very tame here, and are strictly preserved even in the 
garden. As a consequence Peas have not only to be protected before the 
plants appear, but occasionally they have to be kept netted until the 
pods are ready for picking, when sparrows and chaffinches attack them. 
Pheasants are extremely fond of some yellow flowers, notably Doronicum 
