THE COTTAGE GARDENER. 
July 3. 
234 
not sure of the difference yet. Scheeria Mexicana, and 
a seedling Heath, called Spencerianum, with rosy flowers 
and an excellent habit, were shown by Mr. Glending. 
The Messrs. Rollison showed a Begonia splendida, 
clothed with crimson hairs; a new Cypripedivm, and 
a new Dendrobium after secundum; and Mr. Hender¬ 
son sent a beautiful-leaved Gordonia, from China. Then 
there were several of those straightforward-looking 
Gloxinias, which turn up the flowers to be looked at, 
from Tooting and Pine-Apple Place; but I must see 
them again before I decide on their merits. They are 
certainly very pretty, but not so new as this season, 
as I see lots of them at Mr. Jackson’s, of Kingston, 
which he had from the continent last year in large 
plants. Mr. Ingram had an improvement on Achimines 
piota — one with a crimson back to it—a cross, no 
doubt. A Petunia, after my Shrubland Bose, from 
Mr. Westwood, of Acton. If it beds well, it will put 
my credit in that strain on the shelf for ever; and I 
hope it will have as large a circulation ; and that, when 
all his customers are well served, he will send me a 
plant of it for nothing, and pay the carriage, too, to my 
very door. It would only be paying me a compliment 
as being the great advocate for that strain with which I 
pushed the florist’s Petunias out of date, and never 
ceased till I enlisted the first ranks in science to my 
view of a good Petunia. D. Beaton. 
Photographic Portraits of Ferns. —Among other 
objects of interest shown at the conversazione of the 
Royal Society, last week, were a series of photographic 
copies of the magnetic registers at the Royal Observa¬ 
tory. These were of special interest in a double point 
of view, "both as copies of photographs produced by 
artificial light, and as copies of records far too important 
in their bearing upon magnetic inquiry to risk the 
casualties of an engraver’s office, and too nice in their 
details to be of value unless impressed as fac-similies. 
The perfection to which these copies have been brought 
by Mr. Glaisher leaves little to be desired, many of 
them, even, being more vivid than the originals, the 
multiplication of which promises to be of scarcely less 
importance than the first application of photography to 
the registration of the magnets, which until then had 
been recorded by the usual method of observation, and 
was necessarily wanting to the continuity secured by | 
Mr. Brooke’s method by the application of photography. 
By a modification of the same process there were j 
exhibited a collection of British Ferns, by Mrs. Glaisher, ; 
from specimens selected by Mr. Newman. These ! 
beautiful copies, the size of life, and perfect in all their 
details, promise to be of value to the botanist, to whose j 
requirements they are better adapted than any that have ! 
yet been placed at his command. Their effect is that of 
delicate sepia drawings, and at the same time that the 
venation of the leaves is displayed with the fidelity and 
delicacy of the original, it is, as in Nature, only to bo 
detected on near inspection. Our acquaintance with the 
natural history of the Ferns, and their peculiar elegance 
of form, is likely to be much increased by this valuable 
and interesting series, which, we understand, is in course 
of publication by Mr. Newman. The samo process 
likewise supplied numerous copies of snow crystals, as 
observed by Mr. Glaisher, and drawn and photographed 
by Mrs. Glaisher. The application of photography in 
this, one of its most elementary but important branches, 
promises to be an important feature in aid of philo¬ 
sophical inquiry, and is well worthy of considerable ex¬ 
tension in its applications.— Athenceum. 
A GOSSIP ABOUT PITS. 
{Continued from page 218.) 
HEATING TITS. 
“ I have a Melon and Cucumber pit, with seven 
lights, length, twenty-six feet four inches; breadth, six 
feet eight inches; depth in front, three feet six inches; 
at back, four feet six inches—built of rough stone, with 
wooden divisions. It has hitherto been worked with 
stable manure and tan ; but we find much difficulty, in 
making a new bed in any of the compartments, in pre¬ 
venting the plants in the others from being burnt. Do 
you recommend a flue carried round—brick or iron ? 
If so, at what depth from the foundations? Any hints 
will oblige, &c.” 
I presume that this pit is heated by tan inside and 
by dung linings outside. If early growth is attempted, 
the temperature would be more dependent on the linings 
outside than upon the tan within. Allowing for soil 
and growing space, the tan will be about thirty inches 
deep at back and twenty inches in front. To maintain 
a genial temperature in that for a long time, and at an 
early period, the linings would have to be strong, and 
the heat would bo more equally diffused to the tan if 
a small flue ran from back to front under each, or every 
second light; or, failing that, a rough flue, made of 
bricks and clinkers, and left as open as possible. I 
have grown Melons and Cucumbers in such a pit, with¬ 
out any fermenting material inside at all; and with 
close walls, four-and-a-half inches wide, and strength- 
I enened with piers of nine inches. The pit inside was 
1 filled nearly to half its depth with clinkers, brickbats, 
&c., as open as they could be packed; on this rough 
gravel was laid, and on that the soil. There were no 
pigeon-holes in the wall, because the manure was to be 
used as brought from the stable, and, therefore, un¬ 
wholesome steam, &c., was to be avoided. There being 
manure to any extent, there was no want of heat unless 
when the weather was so extra severe as to arrest the 
fermenting processes, which was generally taken care 
of by covering the linings proper with immense mounds 
of litter. 
For a pit to be commenced in February or March, I 
do not see why such a pit should not answer well. 
The burning referred to, I look upon as merely the 
result of an imperfect division, or using the material 
inside in a state the reverse of sweet. Even though the 
tan or the dung used be what is technically called 
sweet, that is, free from noxious gases, yet the steam 
proceeding from such a body when shaking it up, so as 
to form a bed, would be apt to scorch the leaves of such 
tender plants as Cucumbers and Melons. There is no 
doubt that the wooden divisions are not close enough, 
and whilst they remain, all openings should be closed 
with moss or clay while a new bed is formiug. Unless 
used when excessively hot, the depth of fermenting 
matters inside could hardly burn the roots of plants with 
a wooden division all through ; but if danger be appre¬ 
hended from this source, it will be advisable to work the 
tan or the dung well before using it. 
I recollect finding such a pit extremely useful—it was 
"divided into three divisions of three lights each, by brick 
divisions of the width of a brick—four-and-a-half inches. 
The centre was begun rather early, and then the two end 
beds acted as linings to the central one, before they 
were used for planting out. It seems probable that a 
more substantial division, or a better preparation of the 
fermenting material used inside, would obviate all the 
difficulty. Where there is plenty of fermenting matter, 
the chief expense of managing such a pit consists in 
the labour, as the manure just gets prepared for the 
kitchen and flower gardens. I also feel a doubt in re¬ 
commending hot-water in lieu of dung—on the mere 
