486 THE COTTAGE GARDENER AND COUNTRY GENTLEMAN'S COMPANION.— September 10, 1856. 
HEATING A GREENHOUSE FROM A KITCHEN 
FIRE. 
“Early this year I built a greenhouse twenty-three feet 
by fourteen feet, about seven feet from the floor to the glass 
at front, and about thirteen feet six inches high at the back. 
When glazed, my next consideration was, How am I to heat 
it? Some of my friends said Mr. W. would do it as well as 
anybody. I spoke to him, and he proposed three-inch flow- 
pipes, and, of course, three-inch return-pipes. I told him 
almost all my acquaintances were opposed to small pipes, 
but he was sure they would be better than the other. The 
house stands south east. The sun is right opposite at ten 
o’clock. One end of it abuts against the gable end of my 
dwelling; the other is glass. I have a glass partition in 
the middle, with a door, making the house into two. I 
have also stop-taps in tlie middle, to conflne my heat to 
the compartment next my dwelling, where I have two Vines 
and a few other things that require a little heat. In the 
other I keep my Geraniums, Fuchsias, &c. 
“From die first, I have been desirous of heating from a 
fire-back boiler, in order to save the expense of a second 
lire. Economy is an important consideration with me, as I 
am but a working man, and the greenhouse nothing more 
than a source of amusement and pleasure. I was told that 
it would answer. A model was made for a« boiler. It is 
about one foot six inches long, twelve inches deep outside, 
nine inches broad at bottom, and six inches broad at top. 
It stands brick on edge from the grate-bottom of the fire¬ 
place, with a flue behind, and a damper to regulate the heat; 
but somehow or other I do not get beat enough ; either the 
boiler, or the pipes, or both are to blame. Some say the 
pipes are too small; some that such a boiler will not do 
for such a place with such small pipes; others say the 
boiler will do with four-inch pipes and a warm-water cistern. 
The water has to travel about seventy-seven feet. The 
pipe starts fpom the boiler five feet from the front of the 
house, then along the front, then the end, back again on the 
end, the front, and the end again to the boiler, which is a long 
way for the water to travel in such a small body, and keep 
hot. One person says it will require high-pressure heat to 
work such pipes. Mr. W., in his turn, says, he is sure they 
will answer ten times better than large pipes; there is less 
water to heat, and the pipes throw heat off sooner. I have 
not paid Mr. W. for the pipes yet, and I should be sorry 
to throw them upon his hands after his trouble. I have 
thought if we could have another sort of boiler to heat 
quicker with the same fire, say with tubes or some other 
way (for our fire is only a cottage fire), so as to keep all safe 
in ordinary cold weather, and set the boiler either in the 
cellar kitchen, or dig three or four feet down in the green¬ 
house, and make a hole through the gable end, so as to have 
the boiler in the greenhouse, and the fire in the kitchen. 
We could also have a flue, or a flue without the boiler; but 
if a boiler, then connect the pipes, and in severe weather 
work the two boilers together. But I am told they would 
not work; the water from the boiler furthest from the pipes 
would pass through the boiler betwixt the pipes, and it not 
making its circuit through the house. 
“ The greatest simplicity must be kept in view, as my 
wife has to attend to the firing during the day, the distance 
of my employment from home preventing me from taking 
any part except at night. I am very wishful to use the 
house fire for greenhouse purposes, it, is so very convenient, 
and gives no trouble, and can keep a little heat in one 
bouse to get anything forward without the least trouble, 
when beat is not wanted in the other.— John Burrow.” 
[We can hardly make out your case ; but you must write 
again if we do not meet it. 
1. In large kitchen fireplaces the heat from the boiler 
behind it, to heat a house, can often be used very 
economically, as, from the quantity of fuel used, the water 
is seldom cool, and enough of heat, or nearly so, can be 
thrown into the glass bouse in the evening to keep it safe 
for the night. We presume your boiler is one of the com¬ 
mon sort, placed at the back and end of a fireplace, with the 
difference that you have a flue all round it. We presume, 
also, that when you have a fire at night, you have some 
contrivance in the way of a door or damper in front, so that 
the fire then shall act chiefly on the boiler, instead of 
heating, as it would do unnecessarily, the living-room, if 
the fire was burning in the open grate. You do not say 
what heat you can obtain in your boiler; but if you can 
easily heat that to near or quite to the boiling point, there 
can be no difficulty in heating your houses if you can keep 
up the heat in your, boiler, if the pipes, &c., are as they 
ought to he. 
A You have not said whether your boiler opens with a 
lid at the top, and is there supplied with water, or has a 
close top, and is fed from a cistern at a higher level by 
means of a communicating pipe. This will make much 
difference as to the way in which the pipes must be 
placed. You would see a description by our coadjutor, Mr. 
Robson, the other week, of the first mode of circulating the. 
water on a level from the boiler to a cistern, and returning 
from the cistern to the boiler. Now, if your boiler has an 
open lid, you cannot do better than take your upper pipes 
on a level to a cistern at the farther extremity, and from 
thence return to near the bottom of the boiler. If you 
have not a cistern there, have at least an open pipe, to pre¬ 
vent any accumulation of air. We think there must be some¬ 
thing amiss in the placing of your pipes if they do not get 
hot. If your boiler has a close top, and is fed by a con¬ 
necting pipe at some height, then your flow-pipes may 
rise from the boiler to the farther extremity, provided the 
highest point is lower than the supply-cistern, and at that 
highest point an air-pipe is fixed, to prevent any air accu¬ 
mulating; for if ever air gets fixed between two columns of 
water, you may as well attempt to make the water pass 
through a solid block of marble. For such small pipes as 
you have this last plan would answer best, as the pressure 
would cause a quicker circulation, and the air-pipe at the 
highest point would prevent air accumulating. 
8. Mr. W. is right as to water in small pipes getting 
more quickly heated than in large ones, just as a one-gallon 
kettle is more quickly heated by a similar amount of fuel 
than a five-gallon kettle would be; and this quickly heating 
is of importance where sudden heats to counteract sudden 
frost, as in greenhouses, are required; but for such 
purposes as Vineries the sudden heat is of less consequence, 
as a continuous heat is more necessary ; and pipes that, from 
their size and the limited supply of water in the boiler, are 
easily heated, are just as easily cooled whenever the fuel 
fails to burn. We may be prejudiced, but unless iu extreme 
cases, and where a high pressure must be used, we would 
never adopt one-inch pipes; in ordinary circumstances 
never less than three inches, as, when less than-that, much 
of the force of the circulation is impeded by friction against 
the sides of the pipes. An objection against small pipes, 
even when made very hot by pressure, is, that the extra heat 
has an injurious influence on the character of the atmo¬ 
sphere. Had we piping enough to give the requisite heat, 
we would rather never see the water hotter than 160° to 
170°. Much of the unpleasant feeling in hothouses arises 
from the air next the heating medium being scorched and 
burned. 
4. In a house fourteen feet wide, and supposing the front 
to be partly if not wholly glass, we do not consider that 
three one-inch pipes, or rather, six one-inch pipes, would 
present enough of heating surface to maintain a high 
temperature unless they were made very hot; but if they 
did well we should deem them sufficient to keep out frost, 
unless in extreme cases, when part of the glass would be 
covered. The covering, even of the front glass, would 
make a great difference on a frosty night, and soon save 
the covering in fuel, while the plants would he healthier by 
the pipes not being made extra hot. 
5. A small tubular boiler, or a saddle-backed one, vfould 
easily heat such a house, and it could be so arranged as to 
work in unison with, or separate from, the present one; 
but we could not well advise on the position of such a 
boiler unless we either saw the place or had accurate 
drawings. If you ever resolved on having such a boiler, we 
think you would only make the, matter intricate by working 
both at once, though there can be no doubt as to the 
possibility of doing so. If ever you should do so, it would 
be advisable to take the flue from the furnace through your 
Yinery part, as that will give you more heat there. 
0. Of course, you will not only have stop-cocks at your 
division, but a connecting pipe between the flows and 
