THE COTTAGE GARDENER. 
Ekuruaky in. 
;J0() 
unci 8il. for ntteiulance per ilaj', are llio average expenses 
during tlie whole year, and not the expenses for days 
of extra cold, 1 shall leave for others to determine, 
and for IMessrs. Weeks’ to exjilain. If the stated sum 
refer to the average of the year, the economy, tlioiigh 
striking, will not be so wonderful; as, if such a sum for 
fuel would do in frosty weather, then the annual expense 
would still be further diminished from a third to one-half. 
Such estimates arc difficult to make, unless extending 
over long periods, for every one conversant with the 
matter knows, that under the general modes of heating ! 
practised, more fuel may be wanted in one week than 
W'ould suffice for many weeks at another time. 
In all such matters, considerable allowance should be 
made for the statements of men who are earnest en¬ 
thusiasts in their profession, and who thoroughly believe 
they have effected a great improvement, and made a j 
valuable discovery. Without that enthusiasm, there may 
he respectable proficiency in the knowledge of the past; , 
but there will be few advancements upon tlie intelligence ; 
of the present. The enthusiast is often styled a visionary | 
through a part or the whole of his career; but without 
his earnestness, we should have hut few eras to record in 
the annals of ])rogres3. Without endorsing what has i 
been advanced in favour of the one-boiler system, yet, 
lately having passed an hour at the establishment of 
Messrs. Weeks’, attended by Mr Rosenberg, the very 
intelligent horticultural manager, my present impression 
decidedly is, that for all similar large establishments this 
one-boiler system is a movedn the right direction, and 
that some of the objections are either based on miscon¬ 
ceptions, or refer to mere matters of detail, rather than 
those of the principle involved. 
Eor instance, a correspondent, page 78, Yol. XIV., 
because oOOO feet of pipe are heated, comes to the con¬ 
clusion, “ that the extreme eud of the ])ipo must necessa¬ 
rily he 5000 feet from the end of the boiler. In other 
w'ords, the w'ater in the pipes would have to circulate 
that distance before returning into the boiler again.” 
Now, it appeared to me that there could hardly be a 
point in the whole establishment where the water w'ould 
be 500 feet from the boiler. This w’ill at once be seen ■ 
by the published plans of the position of the glass- ' 
houses. The show-house, &c., next the King’s Road, , 
may be considered as the end of an oblong parallelo- , 
gram,'along the sides of which the houses and pits are 
arranged, leaving a space free of buildings in the centre. , 
On one side, behind the show-house, (the side appropri- ' 
ated to tropical plants,) the furnace and boiler are situ¬ 
ated. Erom the boiler proceed two flow and two return- : 
])ipes. One of these, a flow and return, jiroceeds right . 
to the extremity of the side of the square devoted cliiefly ^ 
to tropical vegetation ; the other jiasses through the 
show-house, and along the other side of the square, 
where hardier things, as Epacris, Heaths, Fuchsias, &c., 
j are chiefly grown. Roth these flow-pipes rit^e, though j 
I almost imperce])tibly, to the farther extremity, and there i 
j have an air-pipe attached. F.ven with such a powerful ■ 
boiler its range of action is limited. Mr. Rosenberg ' 
! showed me the point beyond which the heated w'ater in I 
j the flow-pipe would not pass; and the return was made 
I at that point, namely, fltio feet from the boiler. \Vilhin 
I that distance from the boiler they had yet found no 
! limits to its power, in heating houses, to the right and to 
j the Icit, of the main flow and return-pi])cs, giving bot- 
, tom and top-heat at will, and the ])ipes placed in almost 
I all conceivable shapes, as stacks, jiillars, &c. Several of 
: these, quite cool, were quickly heated, to oblige me, by 
j turning a cock or a valve. 1 had long known how small 
I a pipe or opening w'as necessary for this purpose when 
I })roperly placed. 
i It will now, I trust, be clearly seen, that the whole 
I parallelogram of houses and juts is heated by a flow and 
! return-pipe passing right through each side. It will. 
also, he seen that in mild w’eathcr the flow that passes 
through the hardier departments may be shut oil’at w ill. 
These of themselves, however, give off comparatively so 
little heat as not to be injurious. 'J'he temperature of 
the particular house is regulated by bringing its own 
proper pipes into connection with the main flow and 
return. At the extremity of the cool side, we found a 
small house for forcing flowers, &c. This has been ob¬ 
jected to as great waste; because, before it can be 
lieated, the water must ])ass where it is not wanted 
often—through more than flDU feet, and return as far. 
I believe the object to have been to show that at such a 
distance a forcing temperature could be maintained, 
while all the houses between it and the boiler were com¬ 
paratively cool. As a matter of mere economy, tlie 
forcing of these flowers might have been effected on the 
tropical side of the square. It has, also, been objected, 
that before you can give a desirable temperature to any 
one house, on any one side, you must first heat some¬ 
thing like 700 feet of flow and return-pipe, and that, if 
this is simplicity, it is not economy. True, so far; but 
then, the general arrangements here are such that the 
houses that require similar temperature stand on one 
side of the square, and desirable difierences can be given 
by the amount of piping in the house, and the admission 
or not to it of the heated water. iMr. Weeks’ could gain 
nothing by a different arrangement. In a private estab¬ 
lishment, these main flow and returns could easily be 
separated into several divisions ; and even this objection 
wmuld then fall to the ground, by making those divisions 
next tlie boiler the first to be heated. 
“ Allowing,” say others, “ that something is gained in 
fuel, and less attendance in firing, by the one-boiler sys¬ 
tem, this is more than neutralized by the extra attend¬ 
ance upon valves; and this expense, at AT 10s. or 
each, would soon mount up to the expense of separate 
boilers.” I have had something to do with stop-eocks 
and valves, and found all trouble with them a bagatelle 
in comparison with separate furnaces. The expense of 
costly valves is a more serious matter; but what neces¬ 
sity for such cost? I know not what Mr. Weeks’ may 
charge; but I sbould hesitate to give him any such 
amount as the above. Wooden plugs, in many cases, 
with holes slit in their sides, answer equally well; and 
in many of the main houses, a pipe one-inch-and-a-half 
or one inch in diameter, with a stop cock, answered all 
the purpose, and that could not require an outlay of 
many shillings. Were I to take out a patent, (and J 
give the idea gratis to the hot-water professors,) 1 would 
use this simple means for effecting divisions, and render¬ 
ing each division perfect in itself, instead of the costly 
means now often employed, having proved, as far back 
as Mr. Weeks’ father’s time, how small an opening w’as 
sufficient to give a good circulation to heated water. 
Rut the question of economy itself, as to the constunp- 
tion of fuel by one large, powerful boiler, as contrasted 
with a number of smaller ones, is doubted by some of 
our friends, for whoso practical opinion I have the 
highest possible value. They tell us, tliat a given quantity 
of fuel contains only a certain amount of heat; and a 
given quantity of water will require a certain quantity 
of that fuel to raise it -to a certain temperature; and, 
provided boilers are so placed as to receive the same 
amount of heat from that lire, there can bo little 
difference in their capabilities, as the loss can only be 
what is absorbed by the surrounding brickwork, or gets 
out at the furnace-doors, or mounts up the chimney; 
all of which are so far correct: and many, like the cor¬ 
respondent alluded to, though believing that the power 
of a boiler is less owing to its size than the surface ex¬ 
posed to the direct action of the fire, cannot conceive 
“ how it is possible there could be such an amazing 
difl’erence in the amount of surface exposed to the action 
of the fire in two boilers nearly of the same size.” 
I 
