February 25, 1886.] 
JOURNAL OF HORTICULTURE AND COTTAGE GARDENER. 
157 
The editor has, however, found little occasion to alter or add to his father’s 
work, and with the exception of two or three small chapters, such as those 
on “ Cordon Trees ” and “ Seedling Pears,” very little is added, for as it 
is stated in the preface, “ Trees do not change their nature, and the rules 
for their cultivation in one year, if sound, must be the same in all suc¬ 
ceeding years.” Amateurs and others may rely that the instruction is 
sound, for it was derived from a life devoted to the study and culture of 
fruit trees, and abounds in those useful practical hints upon apparently 
small matters that so often remove difficulties from the paths of the 
experienced. 
Much attention is given to Pears and Apples, which are fully treated 
of for all their various purposes as pyramids, bushes, cordons, on various 
stocks, gathering the fruit, &c. Chapters are also devoted to Plums, 
Cherries, Filberts and Nuts. Then in dealing with general culture there 
are chapters upon “ Seedling Fruits,” “ Pyramid Orchards,” “ Double 
Grafting of Fruit Trees,” and many other subjects of a similarly 
interesting and important character. 
In several respects the book has been considerably improved, the page 
is enlarged, a bolder type is employed, and it is tastefully bound in brown 
cloth with gilt lettering. 
A COMPARISON OF MANURES FOR THE GARDEN AND 
ORCHARD. 
[A paper by Professor G. C. Caldwell, Ithaca, New York, read before the Massachusetts 
Horticultural Society.] 
(Continued f rom page 130.') 
That the presence of decaying vegetable matters or of humus in the 
soil does increase the proportion of carbonic acid there is fully shown by 
analysis of the air in the pores of the soil. The air above the soil contains 
three parts of carbonic acid in 10,000, while that in the soil may contain 
ordinarily 100 parts in 10,000; and, moreover, such richness in carbonic 
acid is found only in the air of soils containing humus. A rich dressing of 
stable manure, or, in other words, a large addition of decaying, humus¬ 
forming substance, largely increases the quantity of free carbonic acid in 
the soil. An Asparagus bed that had not been manured for a year con¬ 
tained in the air in the pores of the soil 122 parts of carbonic acid in 10,000, 
but when recently manured 233 parts. Another, a surface soil rich in 
humus, had 540 parts of carbonic acid, a newly manured sandy field 333 
parts, and the same soil, in wet weather, 1413 parts of carbonic acid in 
10,000 of its air. 
This function of the humus of the soil can also come into use with 
respect to the plant food added in manures. To me, one of the most 
interesting properties of soil is that remarkable power it has of absorbing 
certain valuable plant nutrients, holding them in a difficultly soluble con¬ 
dition near the surface, so that, however much rain may leach through 
the ground, they will be only very slowly carried down deeper, or washed 
out altogether. Thus the soil behaves with phosphoric acid, with potash, 
and with the ammonia that is so valuble for its nitrogen. For these three 
substances any arable soil that is not too sandy is a most trustworthy 
savings-bank. Therefore, although we should make much account in 
buying a fertiliser of the proportion of soluble phosphoric acid, or potash, 
or nitrogen compounds in it, yet in all probability, to say the least, our 
crops take up but a little of these nutrients before they are changed by this 
fixing power of the soil into a difficultly soluble condition. 
Why, then, it will naturally be asked, should we pay 10 cents a pound 
or more for soluble phosphoric acid when we can get good insoluble acid 
for 6 cents or less, if what we put on the soil as soluble so soon becomes 
insoluble ? For this reason, partly, that the even distribution of the food 
through the soil is a matter of much importance. Anyone can easily under¬ 
stand that if a bottle of the much-advertised, and I suppose very useful 
tonic, Horsford’s acid phosphate, were poured over half a bushel of soil, 
and washed in with a slight drenching of water, phosphoric acid would be 
far more thoroughly mixed with that soil than, by any reasonable amount 
of stirring such as one could afford to give to a cultivated field, he could 
distribute 2 ozs. of dry superphosphate through the same quantity of soil. 
So, when 400 lbs. of superphosphate are applied to an acre of soil, in spite 
of the best of the usual cultivation that could be given to that soil the 
fertiliser would remain in little scattered particles here and there ; but let 
the rain take it into solution for a short time, and distribute it over the 
surfaces of many hundred thousand particles of soil, so that the feeding 
rootlets find it wherever they go, and how much wider and more even the 
mixing of the fertiliser with the soil will be ; and yet, so quickly does the 
soil seize hold of this travelling plant food, and insolubilise it, if I may 
borrow a very convenient French word with a very plain meaning, that it 
cannot stray far off. 
Practically, then, every crop has to procure all its phosphoric acid, all its 
potash, and a part at least of its nitrogen, from difficultly soluble compounds 
in the soil ; and I think it is now easy to understand why, as so often ob¬ 
served, commercial fertilisers do their best work when used with stable 
manure : the abundance of carbonic acid generated by the fresh application 
of such manure assists in the re-solution of the insolubilised phosphoric acid 
and potash of the commercial manure, as well as of the difficultly soluble 
native food of the soil. Some writers consider this to be such an important 
function of stable manure that they condemn the practice of allowing it to 
rot in the yard at all; they would have all the decay go on in the field, j ust 
where the products of this decay are needed for their action on the soil. It 
was somewhat interesting as well as amusing, while I was writing this, to 
meet with the statement in an English paper that a patent had been taken 
out in England for charging a soil with carbonic acid through pipes laid 
near the surface. A few good results of such a system would be worth 
more in illustration of the principle that I have been explaining than the 
patent will ever be worth to the inventor. No results are given, but you 
eee that it is exactly what Stoeckhardt did, and I have no doubt that it 
would increase the yield of crops ; but as long as we can still get hold of 
any humus-forming material at reasonable rates, we have a far cheaper 
method of attaining the same «.ad. 
There are other ways in which humus may, and doubtless does, favour 
the production of crops; but, to my thinking, all of them taken together 
do not sum up for so much as does this one way that I have been speaking 
of. 
We can compare stable or other animal manures in another way that 
may explain the reason why less satisfactory results are sometimes obtained 
with the latter; I refer to the comparative cost of plant food in the two 
kinds of manure. You are aware that the Directors of the Experiment 
Stations of Massachusets, Connecticut, and New Jersey have, in the past 
few years, conferred together in the spring to determine what may be con¬ 
sidered as a fair valuation per pound of nitrogen, phosphoric acid, and 
potash, in their various degrees of solubility as found in these manures. 
The figures thus given represent the retail cost of these substances, in the 
markets of the State where they are sold as raw materials to be worked up 
into the various brands of fertilisers offered for sale during the year. 
On the basis of this scale of values adopted for 1884 I think it is fair to 
assume that when a gardener or a farmer buys potash in a commercial 
fertiliser, with the same degree of solubility and availability for plant food 
as in ordinary animal manures or other animal waste used for manure, he 
will have to pay at least five cents a pound for that potash; for phosphoric 
acid of like solubility and availability as in these domestic manures he 
would pay about nine cents a pound, and for nitrogen, sixteen if not eighteen 
cents ; I take the lower figure to be sure that I am within bounds. 
(To be continued.) 
POTATOES FOR EXHIBITION. 
Of late years I have not been able to take an active part in 
the various Potato competitions, not, however, from any lack of 
enthusiasm in the matter, but simply because there are too many 
other and more important duties requiring my attention. Not only 
must an intending prizewinner be prepared to devote much extra 
attention to any kind of vegetable with which he hopes to excel, 
but he must also be prepared for many disappointments, this being 
in each instance most apparent in the cultivation of prize Potatoes. 
Under ordinary culture good useful crops of tubers may be obtained, 
but it is only by extraordinary culture that those extraordinarily 
line and handsome samples are secured. Even with the most skilful 
treatment failures will occur, and this will partially account for the 
“ ups and downs ” of various well-known exhibitors. Those, then, 
who, like myself, are unable to devote plenty of time, space, and 
manure to the cultivation of show Potatoes may well follow my 
example and postpone the attempt till such times as the fates are 
more propitious. It is the mixing up the show Potatoes with 
those intended solely for the table—or, rather, the unwise pre¬ 
ponderance of the former over the latter—that in many cases 
brings the show sorts into such contempt with employers, who may 
not object to a few rows of fancy sorts being grown, but rightly 
complain when they are called upon to eat them. The quarter 
devoted to show Potatoes should also be known as the trial ground 
of new sorts, as it is only by a fair trial that anyone can discover a 
really serviceable variety to replace one of the by no means perfect 
table sorts that may be found suited to that particular garden soil. 
Here, for instance, we are obliged to plant Scotch Champion very 
extensively, but I am in hopes of eventually replacing it with one 
less ugly, therefore less wasteful, but possessing the more pleasing 
characteristics of our old favourite. Magnum Bonum we find 
invaluable, being invariably of the best table quality ; yet in a list 
kindly submitted to me by a friend in Kent, and to which I shall 
allude at length, it has a black mark against it, this denoting inferior 
quality, and I mention it here to strengthen my argument that we 
must rely principally upon ourselves to discern which suit us best, 
this necessitating a trial. 
Although not an actual exhibitor of Potatoes, I contrive to 
“ keep touch ” with my old hobby, this being principally accom¬ 
plished by maintaining a correspondence with old friendly rivals, 
notably Mr. C. Howard of Bridge, near Canterbury. Mr. Howard 
is an amateur Potato enthusiast, who devotes his leisure time to the 
cultivation of the best show sorts—and by best I mean only those 
that are both handsome in appearance and good in quality. His 
1885 record is a good one, as out of thirty-two lots staged at 
different shows, including the National, he won twenty-seven 
prizes, sixteen of these being firsts Every season he tries 
several new sorts, the weeding out process being also well attended 
to. Last season four dozen varieties were grown, and twenty of 
these are now condemned, principally owing to the quality being 
second rate or even worse. The sorts grown for the last time in 
1885 were Cardinal, Clyffe Hall, Early Rose, Edgcott Purple, 
Edgcott Seedling, Grampian, International Kidney, Magnet, 
Magnum Bonum, Pride of America, Prime Minister, Prizetaker, 
Purple King, Radstock Beauty, Red Emperor, Snowdrop (a sort 
not distinguishable from Snowflake), Sukreta, Victory, and 
Vermont Champion, also Synonymous and Idaho. Many of the 
foregoing are described in the catalogues as being of excellent 
quality, but in all probability the general verdict on them will 
eventually coincide with Mr. Howard’s. 
The wholesale condemnation of show varieties by non-exhibi- 
