604 
THE GARDENING WORLD 
May 21, 1898. 
although, when planted on the banks of a running 
stream the flowers and growth are much finer. 
Another good plant is Euonymus radicans variegata, 
of which we learnt to our cost the rabbits are very 
partial to, so that wherever these rodents have 
access it is inadmissible, for they eat it off faster 
than it grows. The sweet Woodruff (Asperula 
odorata) has a good effect under the shade of smaller 
growing trees and shrubs. Where the space to be 
covered is of only limited area, we have often when 
passing patches of this after a warm shower been at 
a loss, till we discovered its presence, to think where 
the smell of new made hay was coming from. When 
in flower it is one of the prettiest white flowers 
imaginable. 
Then there are again the Vincas, the large com¬ 
mon one (V major), being the best. Of this there is 
a beautiful golden margined variety. The type will 
grow anywhere and in almost anything ; but about 
the end of the present month they are apt to get a 
bit shabby. If so, cut them over and they speedily 
furnish the ground again. Vinca minor, and its 
silvery variegated form are also available; but it 
takes more time to cover the ground with them. To 
give variety in foliage plant among these spreading 
plants a few clumps of the Male Fern (Lastrea 
Filix-Mas), and the sword t<ern (Polystichum 
angulare). The first being quite deciduous will have 
to be cut over in the autumn. As the Ivy grows it 
must be prevented, by cutting it back at intervals, 
from climbing too far up the trees. I have found 
the young strands of Ivy of a year or two’s growth 
much admired when used for decorating church 
pillars on festive occasions.— IF. B. G. 
-- 
GARDENING FOR CHILDREN. 
It has often occurred to me as to whether we are 
giving that encouragement to the younger portion of 
the community we ought to do in gardening. It 
must be clear to all thoughtful and observing minds 
that if you want a profession or art to develop and 
extend then one of the best methods is to encourage 
the rising portion of the community, as it is far 
more easy to bring these to new ideas than those of 
more ripened years. 
This is most forcibly seen in the encouragement 
that is given in schools, &c , with a view to develop 
and bring out the ideas and powers of the young. 
I am aware much is done in industrial schools and 
elsewhere in the way of teaching them horticulture, 
but this does not apply to our village life. It may 
be said here they have an opportunity of learning it 
in their own parents gardens. True, but children 
want encouragement as well as grown-up people. 
There is now a very large number of villages, &c , 
that have their cottage flower shows to encourage the 
love and produce of the garden by the cottager and 
amateur, and I am glad to say they have done noble 
work in many places. But what have these societies 
done to encourage the young ? I say absolutely 
nothing to speak of. Some may say that we give 
prizes to children for collections of wild flowers, 
&c. This is true, but how can this be looked on as 
help towards cultivating a garden ? Often, as I 
look on these when I am judging them at these 
country shows, I am apt to think they do more 
harm than good, seeing that they encourage these 
children to rob the hedgerows, &c., of much 
beauty to bring to shows to answer no good end. I 
am very doubtful if the collecting of these wild 
flowers has more than one end, namely, that of 
obtaining the prize. 
If our flower shows are to do the work they have 
done in the past, in what way could they advance 
the cause better than by giving prizes to the young 
for material cultivated by themselves ? 
To illustrate my idea, what could encourage them 
better than by offering three prizes, for, say, three or 
four plants of any kind grown in pots ? Or again 
for the best produce of any kind in the way of vege¬ 
tables ? If something as a change is wanted prizes 
might be offered for a bunch of cut flowers obtained 
from plants grown by the exhibitor. Another way of 
stimulating the young is to offer prizes for a given 
piece of ground which has the best vegetables grow¬ 
ing on it and to be cultivated by the one competing. 
Some may say they doubt whether many of these 
may be obtained honourably. Be this as it may, I 
have quite as much faith in children's honourable¬ 
ness as in those of more ripened years in such 
matters. Why could not the Gardeners’ Mutual 
Improvement Societies adopt something of the kind 
for their younger members ? 
I note the mutual society at Sherborne does this 
at their annual exhibition, and it is gratifying to see 
that Chard Flower and Fruit Society has adopted 
the idea by offering prizes for three pot plants 
grown by children under fourteen years of age. 
This is the way to infuse a love into, and to extend 
the art of gardening in the future.— J. Crook. 
THE WORKING VALUE OF FUELS. 
In some experiments carried on at the New York 
State Veterinary College it was found that the heat 
lost by ventilation was 39 per cent, of the whole, and 
my attention has been called to the fact that these 
figures, which may be taken as correct, differ 
seriously from those given in my book on the “ Com¬ 
mercial Uses of Coal Gas,” where the amount lost 
in Messrs. Walker’s bottling stores is given as vary¬ 
ing from 22$ to 25 per cent. The explanation is 
simple—the minimum ventilation required in living 
rooms is 500 cubic ft. of air per hour for each adult; 
in bottling stores only a fraction of this is required, 
in fact, no provision whatever is made for ventila¬ 
tion, and all which takes place occurs from leakages 
and the constant opening of doors for the passage of 
trucks and barrels. The figures given by me are 
clearly stated as being observed results in practice in 
bottling stores only. I had no opportunity before 
the book was published of making exact experiments 
in living rooms, these being very difficult, if not im¬ 
possible, under ordinary conditions in any house, the 
speed of the air currents in the flues varying almost 
from minute to minute. 
Recent experiments in rooms where the ventilation 
is controlled and can be measured have established a 
rule which may be safely relied on for every practical 
purpose. The accepted standard is the British 
Thermal unit, i.e., the amount of heat necessary to 
raise the temperature of one pound of water one 
degree Fahrenheit, and one unit is required per hour 
for each degree rise of temperature over the outside 
for each square ft. of glass, or for every 4 square ft. 
of exposed wall, and two-thirds more for the loss of 
beat by ventilation in ordinary living rooms. The 
loss of heat in living rooms is an unknown quantity, 
as it varies in every room, and in the same room from 
hour to hour, but taking the theoretical value of coal 
gas at 660 British Thermal units per cubic ft., that 
of coal 13,000 units per lb., and of coke 10,000 units 
per lb., it becomes easy to calculate the effective 
value, and the loss of heat in different systems. 
A flueless gas stove may be taken as the highest 
type of efficiency, and using this 1 cubic ft. of gas 
per hour will be required for every 660 square ft. of 
glass or every 2,680 square ft. of exposed wall, for 
every one degree rise of temperature over the out¬ 
side, and, in addition to this, two-thirds of cubic ft. 
for loss by ventilation. Taking a room 22 ft. square 
and 10 ft. high, with all walls exposed, 2 cubic ft. of 
gas per hour will maintain a rise of three degrees 
over the outside, allowing for the average window 
surface. 
The exact figures for warm air stoves with flues, 
and for open fires, are not available, and perhaps not 
possible, but for average practice, it may be taken 
that nearly one-half the total heat is lost in a warm 
air stove with a flue, and two-thirds with an open 
fire. This can hardly be considered as all loss, as 
the ventilation necessary for comfort and health can¬ 
not be always obtained without some assistance, and 
the so-called loss may be partly taken as useful work 
done. The whole subject is beset with variations 
and difficulties, and any standard can be proved to 
be seriously wrong in individual cases, but the 
figures given may be taken for average work. It 
must be clearly understood that the figures given 
are for maintaining the heat, not for raising the tem¬ 
perature of any room quickly, for which a much 
larger fuel consumption is required. 
Heating Plant Houses. 
These figures work out in practice in greenhouse 
heating, where steady temperatures are required, 
night and day, and the loss from any system of 
boilers or stoves, can be readily calculated, a matter 
of interest to nurserymen whose fuel consumption is 
a question of vital importance. The loss in most 
forms of boilers is enormous, and the subject needs 
careful consideration. For this purpose the calcula¬ 
tion is exceedingly simple, on the basis of 10,000 
units per lb. of coke. One pound of coke burnt per 
hour will give a rise of 10 degrees for every 1,000 sq. 
ft. of glass, or 4,000 sq. ft of exposed wall, not allow¬ 
ing for loss by ventilation. For this one-half more 
fuel must be allowed; this gives us the maximum 
possible duty, and a comparison with the fuel burnt 
gives the waste. 
Where the fuel heat is not utilised, there is no 
doubt that at least 50 to 60 per cent, of the fuel is 
completely wasted in most of the systems at present 
in use, and the value of the fuel is not considered as 
it should be. In my own case, with a Chatsworth 
boiler, burning gas coke, and heating a range of 
houses 45 x 30 ft., one-half of which is kept at a 
tropical temperature, the flue heat not being used, 
the calculated consumption is 8 lbs. per hour by 
theory, allowing one-eighth loss for wind, as the 
houses are on high ground, and rather exposed 
(this wind allowance will vary in different dis¬ 
tricts). The actual winter average is iif lbs. per 
hour, showing a waste of 31J per cent., nearly 
one-third of the fuel; this being with a first-class 
boiler, clean, well set, carefully fired, and of the 
correct size for its work. It is doubtful if better 
results could be obtained in practice under any 
ordinary conditions. 
The following rule may be taken as a guide for 
coke-fired greenhouse boilers :— 
For every 1,000 sq. ft. of glass, and for every 
4,000 sq. ft. of exposed wall, for each 10° rise of 
temperature over the outside. 
Loss through glass and walls 16 ozs. per hour. 
,, by ventilation .. .. 8 ozs. ,, „ 
„ „ wind (average) .. 3 ozs. 
,, ,, boiler and flue .. 13 ozs. „ ,, 
Total 2$ lbs. 
Three-fourths of the flue loss can be recovered by 
taking these under the beds in the houses. Any fuel 
consumption over this may be taken as waste 
which can be prevented.— Thos. Fletcher, F.C.S. 
INTERESTING PLANTS. 
The third of the series of botanical and horticultural 
demonstrations that has been arranged by the Royal 
Horticultural Society to be given during the year by 
Professor Henslow attracted a capital audience on 
the 10th inst. Philip Crowley, Esq., occupied the 
chair. 
In his opening remarks the lecturer dealt with 
Alpine plants generally—such plants as are found in 
the Arctic and Antarctic regions, and in high alti¬ 
tudes on the rest of the earth’s surface. He said 
that three things were to be noticed about them : — 
first, tney were much dwarfer than other plants ; 
secondly, the flowers were more abundant ; and 
thirdly, more brilliant than those plants in lower 
altitudes. Some families, such as the Primulaceae, 
stood out conspicuously in the Alpine floras. 
Primula Auricula was mentioned as one of the most 
notable plants of this order. The modern race of 
Auriculas was probably derived from several species, 
but the exact parentage of the race was unknown. 
He pointed out that whereas the old Primula Auri¬ 
cula had the normal number of petals—five—the 
modern forms had seven or eight, the increase being 
due to the stimulus of cultivation, the increased 
nutriment given the plant by the cultivator inducing 
the change, which had now become permanent. 
Dr. Weissman believed that no acquired characters 
were hereditary, but he disagreed with this, and the 
Auricula supported his own views that acquired 
characters might be reproduced in the progeny. 
The professor contrasted some of the magnificent 
yellow-flowered forms sent to that day s show by 
Mr. David Storrie with the refined Alpine varieties 
submitted by Mr. Douglas, the latter representing 
the florists’ ideal of refinement. Other plants, such 
as Primula involucrata, P. Sieboldii, and P. farinosa, 
were mentioned, the latter being found in Cumber¬ 
land and also close to the Straits of Magellan. 
The genus Androsace, belonging to the same order 
was also very largely Alpine. There were many 
Saxifragas too, such as S. muscosa, and S. oppositi- 
folia amongst Alpine plants. It was held that the 
climatal conditions were the cause of the dwarfing, 
although the effects of climate were often exemplified 
in other ways. Thus plants which were not woolly 
in the lower altitudes tended to become woolly in 
the higher. Gnaphalium Leontopodium, the Edel¬ 
weiss, was cited as a typical Alpine plant. The 
