AN 
ENCYCLOPADIA 
OF HORTICULTURE. 
117 
Heating— continued. 
Another modification of a saddle boiler is the Cruci- 
form (see Fig. 174). It combines great Heating power 
with economy of fuel; the formation of its flues, in the 
Fic, 174. CRUCIFORM SADDLE BOILER. 
a, Flow Pipe; b,b, Return Pipes; c, c, c, Triangular Flues, 
shape of a cross, being such as conduces to a free circu- 
lation of water, without the disadvantage of resting-places 
being in them for sediment. Approximate Heating 
power is much the same as in the Gold Medal Boiler. 
The Climax is a wrought-iron saddle boiler, somewhat 
like the Gold Medal, but having only two chambers in 
the interior, instead of three. It has a waterway both 
at back and front, and is fed from the top instead of the 
furnace door. This latter arrangement has now been 
introduced into other forms of saddle boilers, it being 
considered advantageous in saving labour in stoking. 
There are various other modifications of the saddle in 
use, where more chambers are made in the crown part 
or on the sides. Those already noticed will be found 
thoroughly efficient, and, not being complicated in con- 
struction, are much to be preferred. 
A powerful boiler for Heating great lengths of piping, 
on account of its form being specially adapted for sus- 
taining heavy pressure, is the Improved Cornish or 
Fig. 175. IMPROVED CORNISH OR TRENTHAM BOILER. 
a, Flow Pipe; b, Return Pipe; c, Furnace Door; d, Upper 
Flue Dae; e, Lower Flue Door and Front Stand ; fs 
Back Stand. 
Trentham Boiler, represented in Fig. 175. It consists of 
two wrought-iron cylinders, strongly riveted together, 
about 2in. of water space being allowed between them. 
The door frame is attached to one end, and the fire 
bars are inside the cylinder near the bottom, which 
forms an ash-pit, the upper, or larger, portion being the 
furnace. In fixing, the boiler is stood on two cast-iron 
stands, the front one forming a frame for the lower flue 
doors. Walls are built clear of the boiler on either side, 
and upper and lower flues formed by a course of fire 
bricks being fixed against the side of the cylinder about 
half-way up; an arch spanning the top from this. The 
heat is conducted through the centre, over the top by 
the upper flue, and then returns by the bottom one to 
Heating —continued. 
the chimney, thus exposing the fullest possible amount 
of water space to the action of the fire. The minimum 
approximate Heating power of this boiler, 5}ft. long by 
3ft. diameter, is given as 2000ft. of 4in. piping; and 
one 8ft. long by 33ft. diameter is calculated to heat 
5500ft. of the same sized pipes. ` 
Tubular boilers are composed of a series of cast-iron 
tubes placed either in an upright or a horizontal direction, 
and connected together for the free circulation of water in 
all parts. Some are cast in one piece—an objectionable 
system, as any defect in casting, or an accident, may cause 
a leakage at any time, which, if serious, would render the 
whole useless. To meet this objection, and effect further 
improvements, Messrs. Weeks and Co., of Chelsea, have 
provided, in their notable and widely-used Duplex Upright 
tubular boilers with diaphragm, a system by which the 
whole may be worked together, or, in the event of an acci- 
dent to one part, that half of the boiler may be removed 
and the other still kept working until repairs are finished. 
Duplicate parts are kept for replacing those which be- 
come defective, without the necessity of substituting a 
new boiler. Water tubes inclose the furnace, and small 
horizontal ones are placed as fire bars. The fuel is 
admitted at a circular hole in- the top, which is provided 
with an iron cover. Rivers’ Patent is a rather expen- 
sive, but a powerful, tubular boiler, which may be prac- 
tically termed indestructible. It has a double row of 
horizontal tubes, forming a semicircle above the fire, 
which is fed from the furnace door. On any one of 
the tubes becoming defective, it can be replaced by a 
duplicate in a very short time, and the Heating con- 
ducted as before. These boilers are in use, in some in- 
stances, where enormous lengths of pipes are connected; 
but it should be stated that they have not been sufficiently 
tried to prove whether they would be equally satisfactory 
in all cases. They are noted for rapid circulation. 
Fic. 176. UPRIGHT CYLINDER BOILER. FRONT ELEVATION. 
For Heating a small or moderate-sized house, such as 
those frequently possessed by amateurs, a portable Upright 
Cylinder Boiler and Furnace, similar to that shown in 
Figs. 176 and 177, is well suited. It may be placed near 
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