20—1846.] 
THE GARDENERS’ CHRONICLE. 
317 
In * The Captain,” less heat will escape by the flue than 
with other boilers, because the heat from the furnace 
will strike directly under the flow-pipe, as seen in 
ig. 1, and then it must pass through the boiler 2 feet 
more before it reaches the flue. 1t will pass chiefly 
along the upper surface directly under the pipes, which 
surface is purposely made descending, thereby detain- 
ing the heat as long as possible inside the boiler, as 
heat descends with difficulty. Notwithstanding the 
ad ges of this g t there will always be an 
immense quantity of heat pass into the flue, as soon as 
the fuel has become ignited throughout, which will gene- 
rally be towards morning, when it is least desirable to 
throw the heat away. To save this, I have in the 
accompanying plan of “The Captain ” shown how the 
ue is to be brought inside the house without the possi- 
bility of damage ; m is a thin metal trough, 12 inches 
Square, open at top ; the flue (also of thin metal) passes 
through this, being clear of it all round, This trough 
is to be wholly, or in part filled with water as required, 
and a cover of some kind (w), or even a roll of coarse 
Canyas, to be used when wanted. The trough should 
be a little clear of the floor, in order that the heat from 
it may be given out from all its faces. If this flue ‘be 
Made quite straight through the houses, the cleaning of 
it out (it not being intended to return, the chimney 
being placed at the far end), will be a very easy matter. 
The sweeper may commence at either end, and draw 
or push the soot to either opening with any of the in- 
struments at present in use in any ordinary chimney, 
From a to o, the height of the boil s 3 feet 10 in. 
From o to p, the length of ditto, 4 
From n ton, andn tog, breadth of front is 19 in., and of side. 
The space all round the boiler, and at top and bottom, 
for water, is generally two inches only, except where 
the sides and top of the furnace slope in, when it be- 
comes rather more: It is not in the boiler-house that 
a large quantity of heated water is wanted. rr ris 
a space of three inches all over and around the boiler 
in every direction, except under it (and it may be under 
it too) for sawdust or any non-conducting material ; the 
masonry is outside of this. ssss is masonry. This 
may be of any thickness ; in the sketch it is only 43 
Inches, or half-b , except where the boiler rests upon 
the wall of the houses, where it is 9 inches thick. 
¿ttis water of the boiler, all round the fire in every 
direction, except the feeding-mouth and ash-pit. y yis 
a stone slab, resting on the sawdust above the boiler, 
with holes 4 inches square, for the pipes to pass through. 
Fig. lisa side view, showing the wall of the house, 
the boiler passing through it, and the flue in its trough, 
&e. —the latter may be brought outside of the houses at 
any part of its progress, if inconvenient to other 
arrangements ; placing the chimney where it comes out, 
with a damper, &e. Fig. 2 is the front view, without 
the masonry, &e. in front. Fig, 3shows * The Cap- 
tain ” completed, except the blower, which can be hung 
high or low, as the draught requires, e will con- 
tinue to draw well after it is choked up with the ashes 
of the fuel consumed. At the last making up of the 
fires at night, rake out the whole fire to within 6 inches 
of the bottom, then add 18 inches deep of fresh fuel, and 
give a brisk draught for half-an-hour or longer, till the 
~ Whole is thoroughly ignited ; then set your draught or 
lessen it, to last out the night, according to the sort of 
uel used. A portion of coke or cinders, or the “ coal 
balls” described by me at page 149, may be used in 
Various proportions with other fuel. It will require a 
little’extra attention at first, till the amount of draught it 
takes is ascertained, which of course will differ with 
different kinds of fuel, There must be a damper in 
the chimney at the further end, and when fresh fuel is 
added a portion may be heaped up from 5 to d, fig. 1st, 
which will enable the gardener to increase his draught 
to any extreme required without wasting heat, for the 
fuel from 6 to d; will absorb the extra heat completely 
on its way to the flue, and by it be rendered fit for im- 
Mediate combustion when raked down into the furnace 
Inits turn. The tools required are a poker, a hoe, and 
a shovel with a narrow blade, the two latter having 
ron handles instead of wood. In increasing its dimen- 
Sions for greater work, I should not recommend its 
being increased in depth. The one in the plan is 24 
inches from the bars on which the fuel rests to the top 
of the neck, which is deep enough for any size, except 
the very largest. In lessening its dimensions as much 
as 4 or 6 inches may be taken off, making the furnace 
about 20 inches deep, and 10 to 12 in diameter at bot- 
tom,which diameter it should keep for 14 inches upward, 
efore its sides incline inward, as in the present plan. 
hatevér the dimensions of the furnace may be, the 
Space for the water all round it should remain the same, 
viz., 2 inches ‘only, The boiler may be made round 
instead of square or angular by those who prefer it.— 
H.J. D. 
ENTOMOLOGY. 
, Treura MACULOSA (the Spotted Garden Gnat).—YThe 
history of the Cabbage Crane-fly has been already given,* 
and having long suspected that there were at least two 
distinct species of these destructive grubs, I placed two 
kinds in flower-pots, with some tufts of Grass, and after 
failing for several years, I at last had the satisfaction of 
Yearing the smaller ones, and found they were the off- 
Spring of T. maeulosa. These larvee are of the same 
dirty earth-brown colour as those of T. oleracea ; but 
ey are only -fourths of an inch long, and as thick 
um large crowquill (fig. 1); they are wrinkled, and 
NE en at rest they contract themselves, drawing in the 
dead aud thoraci ments, so that this portion looks 
s! Chronicle, vol. i, p. 612. 
* Tipula olera 
more like the anal extremity ; the animal, is able, how- 
ever, to thrust out its head and crawl along very well, 
although it is destitute of feet; the head is small, 
brown, and furnished with two black jaws, short an- 
tennee, an believe minute palpi, which is not the 
usual structure of larvæ that change to dipterous flies ; 
two vessels of a pale colour are visible down each side 
of the back, and one in the centre 5 the tail is furnished 
with two divarieating hooks, and two short teeth between 
them ; the stern being truncated (fig. 2), which will 
readily distinguish the larva from that of T, oleracea ; 
it has two large spiracles, with two tubercles below, and 
two fleshy masses, which are capable of great dilatation, 
and assist it essentially in walking. 
In the spring these larvee change to pupz in the 
earth ; they are about the same length as the larvae, 
but scarcely so stout, and of the like dirty colour ; the 
head and thorax are defined, the latter haying a short 
slender horn projecting on each side; the wings are 
| small but distinctly visible, as well as the legs which 
are placed between them ; there is a spiny elevated 
line on either side of the abdomen, each segmen 
having a transverse row of minute spines above, an 
five larger ones beneath ; the penultimate joint is sur- 
rounded by six longer spines and two small ones, and 
the apex produces a large conical process above, and a 
shorter’ one beneath (fig. 3). 
ies are abundant in May aud June in meadows, 
gardens, fields, hedges, and especially on the sea coast. I 
remember haying seen multitudes once on the sand banks 
in the Isle of Portland in the middle of May, also inthe Isle 
of Wight ard on the coast of Suffolk, and I bred several 
last July. The truth is that there must be either two or 
three broods in the year, or a constant succession of 
the flies, although the spring may be the season when 
the greatest number are hatched, but that will vary 
with the temperature ; and I am also inclined to believe 
that many other species of this genus are} equally 
destructive in the garden ; but the larvae so greatly 
resemble each other that it will be only by a better 
knowledge of these insects, to be acquired only by 
breeding them, that we shall be able to ascertain the 
truth. Certainly I do not remember to have seen the 
Tipula maeulosa in my garden near London, but the 
. quadrifaria, an allied species, was very abundant 
there, as well as a larva so similar to the one before 
us that I cannot, in the absence of living specimens for 
comparison, detect any difference. 
H 
T. maculosa of Hoffmannsegg is a pretty Gnat, not 
quite half an inch long; but the wings expand one inch. 
The male is of a fine yellow colour, the black horns are 
longer than the thorax, and taper ; they are 13-jointed ; 
the first joint is elongated ; the second small and eup- 
shaped, all the others are elliptical, with a few bristles 
at the base of each, excepting the apical one, which is 
very minute; head with a large black patch on the 
crown $ forehead conical, with a little black dot on each 
side ; the face forming a cylindrical rostrum, with a 
hairy beak, bearing a black spot on the top ; the palpi 
are longish and black; the eyes are hemispherical and 
black, but there are no ocelli; the thorax is marked 
with three black stripes down the back, the central one 
the shortest, and the sides are spotted with black ; the 
scutel has a black dorsal stripe; the abdomen is linear 
and obtuse, with a row of black spots down the back, 
and smaller brown ones on the sides ; the wings divari- 
eate or rest horizontally on the body; they are of a 
smoky-yellow tint, the costa is yellow, there are an 
areolet, two little stigmatic cells, and seven apical ones; 
balancers brown and capitate ; six long black legs, very 
slender and tapering ; base of thighs pale yellow, and 
of shanks yellowish-brown, The female is rather larger, 
the horns are shorter; the abdomen is fusiform ; the 
apex acuminated, and furnished with two fine sharp 
lateral valves, and a smalier central one ; (fig. 4, the 
female.) The eggs, which are seattered by the female, 
are intensely black, but dull, oval, and spoon-shaped 
(fig. 5) 5 this, however, might arise in my specimens 
from their not being fertile. 
Some idea may be formed from the following data of 
the mischief committed by this insect. On the 23d of 
April I found the grubs at the roots of my Peas. On 
the 29th some had eaten off trusses of flowers in the 
Strawberry beds, close to the crown, retiring after- 
wards just beneath the surface of the earth, and I think 
it was the same or the larvee of T. oleracea which used 
|to cut through the runners of the same plants. The 
first week in May they were not uncommon among the 
roots of the Lilacs and under tufts of Grass. On the 
28th of the same month I observed some recently 
transplanted Lettuces drooping, and on examination I 
found the roots separated from the crown a little below 
the surface, and close by were these grubs, which are 
difficult to detect, owing to their colour and their re- 
maining quite motionless when disturbed. The end 
of July they were eating the roots of Dahlias, Carna- 
tions, and various flowers ; and the 7th of August they 
infested some Potato ground with the T. oleracea larvee, 
after which I lost sight of them. 
Lime-water will not kill them, and the only mode I 
have been able to adopt with any success has been to 
search round sickly plants, and dig up all that have 
been killed by thent, and destroy the culprits ; but this 
must be done speedily, otherwise they will soon decamp 
to feast upon other plants. I should think watering 
with brine, nitrate of soda, or perhaps strong liquid 
manure, would keep them from our crops.— Ruricola. 
THE AMATEUR GARDENER. 
On Stues AND Snatis.—Passing through King Wil- 
liam-street this spring, I observed a splendid brass 
plate at the door of one of its spacious buildings, bear- 
ing this inscription :—“ Office for extirpating all kinds 
of Vermin.” As I presume this comprehensive notice 
includes all pests which erawl or ereep, whether rural 
or metropolitan, I am surprised the Society is not very 
popular. The Gardeners’ Chronicle might save much 
type and paper every week, and the editor much trouble, 
if this patent mode of destroying insects were adopted. 
Perhaps the subject will be soon taken into considera- 
tion by the Royal Agricultural and Horticultural So- 
cieties, and an invention so very important to gardeners 
brought out of its obscurity. 
But, joking apart, knowing no royal or patent mode 
of extirpating things which inerease and multiply every 
ay, we must proceed by ordinary methods, endeavour- 
ing to find out that which is best. To begin with snails 
and slugs. By the former, I mean those with shells, 
and by the latter, those which are not provided with 
such an accommodation. Both kinds are very rapaci- 
ous, and commit sad havoc in a little time, if their in- 
roads are not watched. Snails do not burrow, and 
therefore they are more easily caught. Look for them 
during the winter in the chinks of walls, and the hollows 
of the roots of old trees. If you have Ivy in your 
garden, you will find that it is their favourite resort for 
hybernating, and there you will seldom look in vain. I 
once collected half a bushel of snails from a wall which 
had been covered with Ivy for many years. The fact 
is, these creatures increase very fast in the autumn, 
when the productionsfof the garden being beyond their 
power of doing them much injury, they are allowed to 
crawl with impunity in the rank vegetation. The first 
frosts drive them to their winter quarters, and you will 
find them in large masses, sometimes looking like con- 
glomerate or plum-pudding stone. The winter, there- 
fore, should never be allowed to pass without a search 
being instituted, so that they may be taken in their re- 
treats collectively, by which much loss of time, and 
much vexation, may be prevented in spring. 
In gardens of moderate size, hand-picking is recom- 
mended as the surest mode of keeping under both slugs 
and snails. This may be done in the day-time when 
the weather is moist. In the kitchen-garden you will 
find the enemy at the stems of Lettuces and Cabbages, 
and in the flower-garden among the Box, or at the edges 
of the turf which skirts the beds. Practice will tell 
you where to look, and an experienced eye will allow 
but few to escape, provided time enough is given to the 
work. As slugs burrow in the ground, it will be ne-- 
cessary to trap them. This is done by strewing Cab-- 
bage leaves on the spots they frequent, or where their 
ravages are to be feared. Hand-picking and trapping 
will soon relieve you from the feats which sometimes 
invade the amateur, when in early spring all his handy- 
works are th d with d i In a smal 
garden they may be, and ought to be nearly extirpated, 
and when we see such little spots covered with the 
slimy traces of this foe, we conclude that carelessness 
has secured them an impunity, and favoured their 
But what is to be done with the guilty parties when 
they are in safe custody? This question has sorely 
perplexed many gardeners, especially those of the 
gentler sex. Ladies do not like killing (one TS 
excepted), and such substantial thing: Tajla: 
despatched easily. Slugs have a hide which, 
skin of a rhinoceros, will resist the trend. 1 
foot, If you keep ducks, the matter is i ed, 
for they will eat all you give theme t$ et 1s to 
see a large snail, shell and all, making js. v don. 
the distended neck of a duck. The most y... etful war j 
a LM 
ys 
"E v 
H'OINOXYHO 
SUN 
Tü0uvo 
r 
