548 
THE GARDENERS' 
CHRONICLE. 
[Ava. 15, 
loaded with moisture as it passes into the house. In 
other respects, the figures fully explain themselves. 
The plan which Mr. Mzrx has himself adopted 
is in preparation, and shall, if possible, be given 
next week, together with the details of expense. 
Tn the meanwhile, it may be useful to mention that 
his apparatus was constructed, under his direction, 
y Mr. Promriper, an intelligent working brick- 
layer of Bletchingly, near Reigate, who is perfectly 
acquainted with the principle of the system, and 
who might, therefore, be advantageously consulted 
or employed by those who propose to adopt this 
mode of heating. 
We foresee an inundation of theories as to the 
cause of the Poraro Disease, which everyone 
finds himself capable of explaining, except those who 
have most information about it. We may therefore 
save the time of our readers and correspondents, as 
well as our own, if we take this éarly opportunity 
of expressing our intention of not giving insertion to 
any speculations upon the subject, unless they in- 
volve new matter, and are supported by authenti- 
cated evidence. 
The following causes for the disease have already 
been suggested :— 
1. The bad season of 1845: 
Attacks of parasitical fungi. 
Insects, worms (the idlest of all specu 
lations). 
Frost. 
Lightning. 
Exhausted vitality. 
. Bad cultivation. 
Guano or other manures. 
. Miasmata, such as produce cholera in 
man, and murrain in cattle. 
The last explaining an unknown cause by an un- 
known agency, whose mode of action in the first 
instance is beyond human perception, may be taken 
as the last and best refuge of theorists, forit is alike 
ineapable of proof or disproof. 
Of the remainder we shall only say that they 
appear to us to be all untenable. Even the sea- 
son of 1845, which seemed to us and so many others 
peculiarly suited to bring on the affection, we long 
ago disclaimed as a true cause ; for irresistible evi- 
dence to the contrary accumulated during the 
winter. In fact, no theory of the Potato disease 
will satisfy the conditions of the problem, unless it 
explains the following unquestionable facts :— 
1. It has for some years past been violent in St. 
Helena. 
2. It appeared in the year 1845 at Genoa and 
Lisbon, and at Grahamstown in the Cape Colony, 
exclusively in Potato crops obtained from English 
“seed,” and therefore of the growth of 1844, 
3. It appeared in 1845 in the Bermudas, in fields 
cropped with Potatoes obtained from the United 
States, and not in those which had been cropped 
with Bermuda sets. 
4. It has broken out in New Holland, upon the 
authority of Dr. Francis CAMPBELL, in a letter to 
the Sydney Morning Herald, dated March 18, 1846. 
5. It was little known in bog or moss-land in 
1845, and now has broken out there with as much 
violence as elsewhere. 
6. It is accompanied by an increased excitability 
of the Potatoes both young and old, 
7. It invariably begins as a brown decay of the 
bark of the Potato-stem, under ground, and an inch 
or two above its origin from the old set. To this 
we have never yet found an exception; all the 
blotching and searing of leaves are long posterior 
to this. 
8. It has broken out at-this moment (Aug. 12, 
1846), in crops obtained onwell-drained unmanured 
land from sets imported from Naples, the Azores, 
Oporto, and New Grenada, every one of which 
places was reported to be uninfected. 
Anoruer sale of Mexican Orcas is announced 
for next week. We mention it thus for the purpose 
of stating that Epidendrum erubescens, one of the 
most beautiful species from that country, is among 
the lots. Two orthree Odontoglossums,well worth 
having, are also there, with Barkeria melanocaulon, 
and a very curious new genus called Galeottia 
grandiflora. 
Wealso take the present opportunity of acquaint- 
ing botanists that Messrs. STEVENS will sell in the 
course of September some parcels of dried plants, 
of considerable interest, from the late Mr. Maruews, 
and with them a manuscript Flora Peruviana, in 4 
thick 4to volumes of letter-press, and 1 volume con- 
taining about 100 coloured drawings and sketches. 
This work contains short characters of the plants of 
Peru, which are numbered throughout, and appear 
£o correspond with the dried specimens sent to 
Europe by Mr. Matuews. The letter-press also 
contains a large number of pencil sketches, illus- 
rating the structure of the plants described. 
Is] 
Pap 5 
Can 
SHALLOW PLANTING ON PLATFORMS. 
Many and grievous complaints throughout the king- 
dom have been made about the bad condition of Peaches, 
Nectarines, &e., on the open walls. The old catalogue 
of evils (curled leaves, insects, mildew, &e., together 
with the destruction of whole branches—even whole 
trees) is charged by the sufferers on the late cold and 
damp summer; and, no doubt, that inclement and un- 
usual season had much to do with the affair. However, 
the fitfulness of the British climate is proverbial ; and 
it becomes, in consequence, one of the most important 
duties of the British gardener to provide against such 
inclemencies. 
Having myself escaped the sort of devastation com- 
plained of, I may perhaps be allowed to offer a little ad- 
vice to those who have not studied the subject. I have 
been for many years advocating comparatively shallow 
borders for fruit trees in general, as the basis of all 
acclimatising ; or, in other words, of ripening the wood 
ofthe current year. The principle has been severely 
attacked, and this I lament, not on account of the oppo- 
sition, but because I am persuaded the plan is at least a 
step in the right direction. My platforms are 15 inches 
deep for Peaches. 
Now, I am free to confess that two essential conditions 
are necessary under this mode of border-making, viz., 
the one, that a very sound or rather tenacious loam 
be made use of ; the other, that a barrowful or two of 
dung must be applied, as a top-dressing in hot and dry 
periods. There is, perhaps, no absolute necessity for 
this; yet it is advisable, as adding to the size of the 
fruit, as well as contributing to the stability of the tree. 
This plan, then, I have pursued. And, surely, the 
unusual period of heat and drought which occurred this 
summer was a tolerably severe test of matters of this 
kind ; yet my trees are in most excellent condition. Not 
a leaf injured—in fact, they cannot be better ; and they 
carry, moreover, a fine crop of fruit. Loose sandy soil 
requiring manure is not the thing for the Peach ; if any 
one should adopt the platform mode with such a 
material, he will soon find himself grievously mistaken. 
Let such, however, not blame me. Such a soil will, by 
the aid of manures, produce a gouty and overgrown 
tree, through too rapid an action of the root; and it 
will as readily desert it in the hour of need. 
If it be urged that so shallow a border will not endure 
so long as a deep one, I answer, top dress in due time. 
Trees planted on such borders would enjoy a dressing 
composed of one-half sound loam, and the other half 
any coarse vegetable matter that would insure a con- 
stant porosity, and prevent undue adhesion in the loam. 
The dubbings of hedges, charred, would be excellent. 
However, this would not be required for at least seven 
years after planting. Is not this more reasonable than 
surcharging the tree at first with crude sap, through 
an unmanageable volume of sojl or rich compost? By 
the platform mode, the top-dressing need not be ap- 
plied until the tree actually requires it. 
One of the greatest considerations attached to this 
mode of planting, is the readiness with which Nature 
will heal any blemish that may occur in early spring, 
through insects or a bad state of atmosphere. The tree 
with surface roots will rally again the moment the evil 
is removed ; and why? because there is a lively root 
action ; days—nay, weeks in some cases, before that of 
the tree with deep roots. Now, early-made wood will 
prove early ripened wood, if other appliances are at 
hand; and this brings us at once to the principle on 
which shallow planting is based, viz., ripening the wood. 
The utmost attention ought to be paid to the sum- 
mer management of the young wood. Not a shoot 
more should be left at the final thinning than is required 
for the next year. This is, however not all, for if the 
lower parts of the tree are to receive a fair amount of 
the rising sap, the over luxuriant shoots must be topped 
in due time, Now this should never be done all at 
once; it is a progressive work, and should be per- 
formed at three distinct periods at least, Winter 
pruning is of course necessary, but it can never accom- 
plish what is required in a dwarfing system. 
In addition to this, I am of opinion that a general 
* stopping," as it is termed, would be extremely bene- 
ficial about the period when fruits commence their last 
swelling. It will, I imagine, be found to enhance both 
size and flavour in the fruit, and to promote the ripen- 
ing of the wood. Any fcrther extension of the tree 
after the second week in August cannot be expected to 
produce any real benefit. 
No particular mode of cultivating the Peach will, 
however, be long suecessful without a freedom from 
insects. The aphides frequently commit the most 
ruinous depredations before they are perceived or at- 
tended to. The best way to bid them defiance is to 
syringe with strong tobacco-wat ive even 
ings, as soon as one green-fly can be perceived ; this 
wil admit of no delay, although the enemy 
at the moment appears insignificant. This, with 
the addition of a sulphur mixture, applied like 
paint, will keep any trees absolutely clean, and with 
comparatively little trouble; for if the processes were 
complicated, or required an unusual consumption of 
time, I fear the trees would soon fail. 
Before I conclude these remarks, I may perhaps be 
allowed to say a few words about the use of turfy soil, 
from old rest land. To say that such is absolutely in- 
dispensable is a mistake ; it is, however, complete in 
itself, for the cultivation of our superior fruits. It 
is certainly a rather eostly material, but not so much as 
some would imagine, provided means be taken to com- 
pensate for the removal of it. I have known loamy 
soils, so good, and so deep, that it would scarcely be 
missed ; but on shallow soils the loss is certainly some- 
what serious. However, by the platform mode about & 
tithe part would suffice of what is required to make a , 
border, as it is called ; which border-making I hold to 
be entirely superfluous, unless it be for Vines. In the 
latter case a good portion of turfy matter should by all 
means be applied, if possible. 
For Apples, Pears, Plums, Cherries, &c., there is no 
occasion to use much turf ; something, however, must be 
used to supply its place, or the soil will speedily become 
too adhesive. I have no doubt that charred brash-wood, 
Heather, Fern, or any gross kind of vegetation, intro- 
duced in layers, would be of much service. The dubbings 
of Hedges, Gooseberry and Currant cuttings, too, are 
always at hand. All these articles should, however, 
undergo a charring process, or they will prove too ab- 
sorbent with age. The soil I use for platforms isa 
strong loam, with little or no turf in it. The scouring 
of ditches, in superfluous soil, obtained in lowering the 
headlands of fields, or other improvements ; with this I 
mix brash and strawey long dung from the stable door, 
and I find it everything I could wish.— Robert Erring- 
ton, Oulton Park, July 28. 
ON THE ORGANIC COMPOUNDS WHICH CON: 
STITUTE THE NUTRITIVE PORTIONS OF 
THE POTATO. 
By the Rev. Prof. HENSLOw. 
(Continued from p. 532.) 
I wow pass on to the consideration of gluten 
and other organic substances, composed of four 
elements, and therefore differing materially from 
those which we have been hitherto considering. 
Although they bear no resemblance in chemical 
composition to the membrane composing the 
vegetable tissues, they possess an important influ- 
ence upon the development of those tissues. Four of 
these substances, albumen, fibrin, casein and gluten, 
differ very slightly in chemical composition ; and it is 
asserted they all appear to be oly peculiar modi- 
fications of a common basis named protein. I shall, 
therefore, in this merely popular exposition, speak of 
protein as the sufficient representative of gluten, or of 
whatever other quaternary compound nearly allied to it 
may be formed in the Potato. ts composition ap- 
proaches to C4s O15 Hao Ne ; but, as I find that Liebig 
has given us two formulz for this substance in the very 
same work, I suppose chemists have not yet fully and 
definitively made up their minds about it. This sub- 
stance, when modified under the form of gluten, may very 
readily be obtained from Wheat flour, by simply washing 
a lump of dough for a few minutes, by which means the 
particles of starch are removed, and a clammy mass re- 
mains. It is advisable to wrap the lump in the corner 
of a towel during the early part of the process, and work 
it about under water until a considerable portion of the 
starch has been removed. This lump of gluten before 
you may be stretched and drawn out in all directions;"so 
that when itis held between the eye and the light it some- 
what resemblesa piece of bleached muscle. Itis the mate- 
rial out of which animal muscle is manufactured. Che- 
mists assure us that protein is the basis of certain animal 
matters which bear the very same names as those sub- 
stances which are idered to be modifications of pro- 
tein in the vegetable kingdom. They believe animals have 
not that power which vegetabl sess, of originating 
protein; but that they appropriate it, either directly, by 
feeding on plants, orindirectly,by feeding onanimals whose 
flesh has been already organised from vegetable protein. 
There are certain animal products (as fat, for instance) 
which are composed only. of the three elements found 
in starch, &e. ; but these do not form the tissues of 
which their bodies are made up. It should seem, then, 
that whilst the membrane which forms the tissues of 
plants, is composed of only three elements, the tissues of 
animals are essentially composed of four. These 
tissues, in both kingdoms, include in their interstices or 
cells, a vast variety of compounds which they originate, 
either by effecting the organic combinations which have 
been alluded to, or by modifying such combinations 
when previously formed. Some organic compounds 
have minute proportions of phosphorus, sulphur, and 
other elements, as constituent and essential parts of 
their substance; but I have purposely abstained from. 
noticing these, as they form a very small per centage of 
the whole. I also omit the earthy matters de- 
posited in the form of bones, shells, &c. Some physio- 
logists consider that nitrogen must be assimilated di- 
rectly by animals, for the formation of their tissues; but 
I am not aware that they have sufficiently substan- 
tiated their views, to admit of their being put 
into successful opposition with the opinions of those 
chemists who have arrived at a contrary conclusion 
from evidence afforded them by an immense num- 
ber of experiments. These have been undertaken 
with a skill and perseverance which warrant our 
trusting them, until we shall be assured that still 
greater skill may have been displayed in advancing out 
knowledge of these deep mysteries of nature. 
If the tissues of animals are derived entirely from 
such protein as has been formed by vegetables, we must 
infer that starch and such other organic matters as cone 
tain no nitrogen, can be of no service in nourishing 
our bodies—restricting the meaning of the word “ nou- 
rishment” to the addition of fresh materials, either to 
inerease their substance or to replace portions whieh 
have been removed or wasted. It has also been fully 
demonstrated, that if animals are fed upon such organic 
| matters as starch, sugar, and gum, which contain only 
| 
