404 
THE GARDENERS' 
CHRONICLE. 
[June 20, 
the other things, they deserved not to be overlooked, 
far less ought their common character to be attributed 
to the whole collection. Besides the appearance of a 
collection of fruit, there is another important considera- 
tion, which renders it desirable that collections should 
be encouraged. There are usually plenty of exhibitors 
in the classes of Grapes, Pine-apples, &c. It is some- 
times easy to excel in any one of these under favourable 
circumstances. One man is, perhaps, an enthusiast as 
regards the production of an object, which he makes 
his hobby ; and when this is the case he is likely to be 
successful, and it is well to reward him, because he 
* shows what may be achieved by skill and untiring at- 
tention to a particular object of his cultivation. But 
noblemen and gentlemen cannot afford that attention 
should be paid to one particular object only ; they must 
have a gardener who can grow many kinds of fruit 
in perfection. Therefore the Society should encourage, 
as much as possible, the gardener who aims at produc- 
tention. Now it may sometimes be requisite that an 
hundred or more experiments should be undertaken 
before the correct methods of applying some one of 
hrendaticfuctaval 
glass. By various methods we can Separate the mem- 
branous bladders which contain the grains of starch 
from each other, and at (b) there is one of these blad- 
these principles to practice can e- 
tected. Whilst some are expecting too much of sci. 
ence, there is a vast number more, even among well- 
educated men, who are very ineffieiently impressed with 
anything like a due “perception” of the manner in 
which science should be allowed to direct (if not to dic- 
tate) the course that should be pursued by unscientific 
experimenters, : 4 z 
In offering a Lecture upon certain topics which may 
be considered as bearing directly or indirectly upon 
questions connected with the recent failure of the Po- 
tato crop, I do not profess to have. any fresh facts to 
add to the information which has already been made 
publie. My objectis to give a popular review of the 
nature of the most important organie compounds which 
areto be met with in the Potato ; and to bring before you 
lusi at which some of the most eminent che- 
ing a good collection, seeing that such gard give 
the most satisfaction to their employers. 
The question is—what means can be adopted? The 
regulations as they now stand are quite unobjectionable; 
yet the exhibitions of collections are at almost the 
lowest ebb to which they possibly can arrive. This was 
not always the case ; they once seemed in a fair way to 
attain the highest pitch, 
judges are to blame, and no one else. 
The judges in those days were censured for being too 
liberal in their awards, but they had the table loaded 
with an immense quantity of very fine fruit ; some, o 
course, was not so good, but the bad would doubtless 
have disappeared in a year or two. 
The judges next became extremely critical and penu- 
rious, and now they see the result ; which they might 
have foreseen a twelvemonth ago. Matters have be- 
come worse and worse this season ; and even so patient 
a sufferer as Mr. Spencer is driven into class-showing. 
Mr. Ingram's collection was almost the only one they 
had to consider in that way. It contained five beautiful, 
admirably-grown Queen Pines; some good Grapes, 
Museat of Alexandrias, the best ripened of the sort that 
were exhibited ; Plums, to foree which (even to make 
a variety early in the season) is precarious, and demands 
much skill ; Elton Cherries, not large, but good and 
well-ripened. Altogether, as many of the company re- 
marked, Mr. Ingram's fruit was “fit for a Queev.” It 
is true that a Melon, and some Figs, and White- 
heart Cherries, were not so fine ; but his Peaches were 
good, and his Nectarines handsome, though hardly ripe. 
To this collection the Society's judges would not give 
the highest prize (the Gold Knightian), nor even 
the next (the Gold Banksian), but one neat to 
the very lowest in their gift! namely a Silver 
Gilt Medal, to which the Pines alone would have 
been entitled, had they been exhibited separately. 
And then, again, there was a Pine from Frogmore, 
beautifully grown, and I should thin: a four-pounder, 
If we ask where the judges put it, the answer must be, 
to the bottom of their list, 
This sort of incomprehensible, as well as unfair, 
decision, must of course drive off exhibitors, who 
expeet justice; and if they get that, however unfavour- 
able it may be to them, are contented. That the 
Society's judges mean well, I, who know them, fully 
admit, but that they are capable of executing their duty 
I must, with great respect for them, deny : and I will 
even add that it is quite indispensible that the Society 
should make some change among them when the next 
Season comes.—A Fru ower, but not an Exhibitor. 
E 
ON THE ORGANIC COMPOUNDS WHICH CON- 
STITUTE THE NUTRITIVE PORTIONS OF 
THE POTATO. 
By the Rev. Prof. Hzxsrow. 
Lasr November and December I had an opportunity 
of giving two or three lectures to some friends and 
neighbours on subjects bearing on the Potato question, 
which was then engrossing so much attention. Having 
retained my notes, I have thought it?might be'useful;to 
send you the substance of; those lectures, for such of 
your readers as may be as little acquainted with 
Chemistry or Physiology as myself; and I must run 
the risk of being censured or corrected by those who 
may detect in my any misapprehensi 
may be entertaining of those views which chemists an 
physiologists have of late been laying before us. i 
= 
o 
1s 
not with any desire of converting agriculturists into 
chemists that such popular expositions as these can be 
considered useful. Tt is rather to incline them to 
receive with i ing d the i 
which chemists of good repute may throw out to them 
concerning the methods that should be adopted for 
ascertaining how “sound principles? may be applied 
to the improvement of “approved practices.” Not- 
withstanding much that has confessedly been done 
within the last few years, in convincing practical men 
that they will do wisely to attend to the suggestions 
which science can offer them, it is still too evident 
that much time is lost, and much money wasted in the 
methods frequently taken for arriving’ at conclusions 
which would be far ‘more speedily and readily obtained 
under a good system of spirited and well-directed co- 
operation. It is not one or a dozen failures that should 
so dishearten the practical man as to cause him to faney 
the principles which chemists have established are in- 
correct in theory. The detection of these principles has 
been the slow result of laborious investigation carried 
on for ages ; and every principle has needed a multi- 
tude of experiments to substantiate its iust claims to at- 
he 
mists, and other scientific men, have arrived concerning 
the office which these compounds fulfil in the general 
economy of vegetable and animal life. The more dis- 
tinctly we are enabled to appreciate the value of these 
compounds in relation to the functions of animal nutri- 
tion, the more likely we shall be to form a correct judg- 
ment upon any of the plans that may be suggested 
either as palliatives to the loss that has been incurred, 
or as precautions against any recurrence of so great a 
ealamity. Without dwelling on particulars, which have 
already been well discussed, respecting the methods of 
saving as much as possible of the tainted Potato, or of 
extracting and preparing the uninjured starch which 
it may contain, I shall proceed at once to a considera- 
tion of those two organic substances (starch and gluten) 
upon which the nutritive properties of this tuber chiefly 
depend, The other nutritive compounds which may 
also be detected in the Potato, bear a very small pro- 
portion to its whole weight ; and their chemical com- 
position is either identical, or so nearly identical, with 
one or other of those two, that we need not, in a mere 
popular review, do more than slightly allude to them. 
My remarks will not be confined to points whieh are 
exclusively chemical, but I shall notice some of the 
more i facts and speculati which botanists 
and physiologists have made known to us in reference 
to this subject. It is by obtaining some general notions 
of the bearing of various sciences upon any particular 
question, like the present, that we become hetter quali- 
fied for testing, as well as trusting, the advice of scien 
tifie men, when they propound their schemes for the 
consideration of parties who may be much better a 
quainted than themselves with practical details, and 
mueh better qualified than themselves for ascertaining 
whether their advice is worthy of being adopted ; or, at 
least, whether it may not be so far modified as to be- 
come 50. 
In the first place I would speak somewhat botanically, 
and describe to you the circumstances under which 
starch is to be met with in many plants; and show you 
what are the general forms and appearances it assumes. 
Either starch or some compound, very nearly, or even 
absolutely identical with starch in chemical composi- 
tion, occurs in all plants ; and we may very safely con- 
clude that such compounds must be essential to their 
existence, and to the development of their tissues. I 
must remind you that all plants are largely, and some 
entirely composed of “cellular tissue." This cel. 
lular tissue is formed of an assemblage of microscopi- 
cally minute membranous bladders, When these- 
bladders are detached from each other, they are 
generally more or less spherieal. "They are filled with 
fluid, and by mutual eompression, their surfaces are 
flattened at the places where they touch each other, 
and thus they become many-sided in shape. If a sec- 
tion be made through a mass of cellular tissue, the 
cut surface will present a number of polygonal areas, 
which are more or less regular, in proportion as the 
bladders are more or less uniform in size. At fig. 1 (a) 
[3 
(0000 
b Fig. 1. a 
we have the appearance presented by a very thin slice 
of Potato made with a sharp razor. This may readily be 
seen under lenses of a low power, such as are used in the 
very commonest description of microscopes, The little 
oval and oblong bodies which nearly choke up some of 
the interstices or cells, are grains of starch. Some of 
them float freely in the liquid contained in these cells 5 
but in the example which I now show you, they appear 
to be crowded close to the walls of the cells, and 
leave only’a small area free of them, in the middle of 
each, These grains of starch are so perfectly pellucid, 
as to resemble small rolled and rounded fragments of 
lers rep d under a high power of the microscope. 
We can now perceive that the starch-grains are faintly 
striated or marked (apparently upon their surface), with 
curved lines, and that there is also a dark spot on them 
which is generally placed near one extremity. These 
appearances are connected with the peculiar conditions 
under which the grains have been formed. I do not 
pretend in a lecture like this to enter into much minute 
detail, but I will just remark that the internal structure 
and mode of formation of these grains has largely oc- 
cupied the attention of philosophers ; and I would es- 
pecially notice to you the labours of Mons, Payen, which 
are recorded in the 10th vol. of the “Annales des 
Sciences" for 1838. Should any of you be inclined to 
learn more respecting the position of starch-grai 
than the present sketch can furnish, you will find in M. 
Payen's Memoir very aceurate representations of starch- 
grains taken from 45 different kinds of plants. Each 
grain is composed of a series of layers or coats, one 
over the other, and it is supposed that they have been 
formed by successive depositions of matter, the last being 
the innermost, and the substance of each having been ab- 
sorbed through the little dark spot we noticed on their sur- 
face. If this opinion be correct the outermost coat must 
have been a kind of cell; otherwise the process must have 
taken place by successive depositions externally, after 
the manner of stalaetitie deposits, which there appears to 
be good reasons for not believing to be the ease. In 
order that you may obtain a better general notion of the 
manner in which grains of starch differ in form and 
size in various plants, I have selected four kinds for 
representation, at fig. 2, and they are sketched as 
nearly as possible to their relative proportions, The 
largest (fig. 2 d) are from a varicty of the Potato, and 
attain to seven one-thousandths of an inch in length. 
Those from the Chenopodium Quinoa (c), which M. Payen 
considers to be the smallest known, do not. measure 
more than very nearly seven one-hundred-thousandths of 
an inch. In considering the relative bulks of the grains 
of these two starches we find them bearing about the 
Same proportions to each other as the sun to the earth ! 
The largest grains of the starch called Arrow-root (5) are 
somewhat less than those of the variety of the Potato 
alluded to, and the largest grains of Wheat-starch (a) are 
about two one-thousandths of an inch in length. 
I shall now allude to some of the starches which are 
objects of commercial speculation, and point out to you 
the plants from which they are obtained. 
Starch is only formed within the membranous blad- 
ders that compose the cellular tissue of plants ; but as 
this tissue pervades the whole vegetable structure, the 
starch grains are sometimes aggregated in one part 
and sometimes in another part of plants, in sufficient 
abundance to make it worth while to collect it from 
those parts for economical purposes. It is very largely 
stored up in many seeds, for the use of the young plant 
when it begins to germinate. The starch commonly 
used by washerwomen is prepared from Wheat. 
Starches are also sold which are prepared from Rice 
and Maize, and both these starches are patented. I 
am not aware whether the patents refer to any pecu- 
liarity in the mode of preparing the starch from the 
two last-named descriptions of grain ; but if they merely 
relate to the starches themselves, a very large propor- 
tion of the vegetable kingdom might be thus patented. 
have been shown a starch which the mieroscope 
readily reveals to have been extracted from the tubers 
of Potatoes, and yet the vender professes to sell it as 
the produce of a particular seed. His false statements 
induce his customers to pay about 1500 per cent. more 
than this starch is really worth in the market, though 
probably it is just as good and wholesome as the 
genuine article it professes to represent. But Potato 
starch is largely employed for purposes of adulterating, 
and even for wholly replacing some of the starches of 
commerce, such as sago, arrow-root, tapioca, &c. ‘The 
Horse Chestnut furnishes an excellent starch, and this 
in so great abundance, that I suspect it might very 
readily be procured as a cheap substitute for Wheat. 
starch. I have understood that some washerwomen do 
make use of the Horse Chestnut ; though I believe it is 
rather as a substitute for soda than for the sake of its 
starch, as it contains an abundance of an alkaline material 
p ing abstergent properties. A g toa French 
chemist, Raspail, who has paid much attention to this 
subject, when the Horse Chestnut is reduced to a pulp 
it forms a paste that is well adapted for a certain pro- 
cess in weaving, enabling persons engaged in that art to 
work in drier and more airy situations than they would 
otherwise be able to do, when employing the crdinary 
kinds of paste. He also suggests the possibility of re- 
