8G 
JOURNAL OF HORTICULTURE AND COTTAGE GARDENER. 
[ February 3, 1887. 
bodies of flume, but does not possess the power of preventing a low 
charing combustion, and that steam impelled against a large fire 
increases the violence of the combustion in a remarkable degree.— 
E. Burton. 
influence the draught. These are the reasons why fires burn brighter in 
cold frosty weather than they do when dull and foggy. 
Now, if Mr. Bardney has any more “fogs” floating about the 
furnaces at Norris Green, perhaps he will favour us with then- nature 
and finish this matter. 
Although it may appear to the eye that water is “ completely re¬ 
pulsed by red-hot iron,” and which Mr. Bardney “ maintains,” the gases 
evolved prove conclusively that such is not the case, and that actual 
contact does take place. The intense heat imparted to water by 
plunging a piece of red-hot iron into it will rapidly convert the particles 
immediately surrounding the iron into steam, and at the same time 
dissipate a portion of the air and other gases which have been dissolved 
in the water. Part of the steam acting upon the iron is decomposed 
and the iron oxidised, and thereby liberating the hydrogen, which is 
found in a free state amongst the gases and vapour evolved. 
This means of oxidising iron is an accomplished fact whatever Mr. 
Bardney and others may “ maintain,” and by way of verifying this 
statement I give you the following quotation from “ Wilson’s Inorganic 
Chemistry,” page 179, par. 466 : — “ Iron cannot decompose water at 
ordinary temperatures, but if heated red hot it acts like sodium, with 
this difference, however, that all the hydrogen is evolved from the 
water, none remaining in combination with the metal.” (When sodium 
is put into water only half the hydrogen is evolved, the other half, with 
the oxygen, combining with the metal.) “ This property of water is 
generally illustrated by sending steam through an iron tube like a gun 
barrel placed across a small furnace, when the iron unites with the 
oxygen of the water (steam), and the hydrogen is set free ; but so com¬ 
plicated and troublesome an apparatus is not necessary for the purpose, 
if a bar of iron be raised to a full red heat it will be found to decom¬ 
pose water when plunged below its surface. To prove this, all that is 
needed is to thrust the red-hot bar below the mouth of a gas jar filled 
with water, when bubbles, apparently of ah', will be seen to rise from 
the iron and collect in the upper end of the jar. These bubbles consist of 
hydrogen gas mixed with a little air.” I may also add that the above is 
verified by Buckmaster and Brown. 
But it is not with water we have to deal, but its gaseous form when 
treating it as a supporter of combustion ; and because some of the 
results effected by its use for this purpose are antagonistic to the ex¬ 
pressed opinions of some, they avail themselves of every plausible argu¬ 
ment likely to afford their cause support, while the object for which 
they profess to be contending is allowed to dwindle into a myth. No. 2 
of Mr. Bardney’s questions comes next. He wants to know what effect 
moisture will have upon anthracite coal, coke, and ordinary coal, and 
also upon salts obtained from sulphuric and hydrochloric acids. Anthra¬ 
cite coal is almost entirely composed of carbon, some kinds are wholly so ; 
and the effect upon it I have stated in another article, also the results 
when employed as a supporter of combustion when coal and coke are 
used as fuel. Nevertheless, I may add that coal, being of organic 
origin, contains sulphur, phosphorus, and chlorine, which will be con¬ 
verted into acids when burned with hydro-carbon; yet they will be 
carried away by the draught, or,! at least, most of them. That 
portion which is left will form the salts mentioned by Mr. Bardney. 
But these salts are harmless so far as the bars are concerned, and 
although a deal could be written regarding compounds of this sort 
formed and changes effected, it would have no direct bearing upon the 
subject either pro or con. ; but at the same time it is well to bear in 
mind that water is one of the products of combustion, therefore steam 
would have no effect upon any of the compounds obtained from the 
burning fuel. 
With No. 3 question Mr. Bardney finishes his literary thunderbolt, 
and this he has hurled at the head of “ Thinker.” He asks, “ Why 
does a fire burn more brightly on a cold frosty night than it does on 
one dull, damp, and foggy ? ” Gases are elastic fluids, and are far more 
susceptible of changes of temperature and pressure than either liquids 
or bodies. The normal pressure of the atmosphere is 760 millimetres, 
and which is equal to almost 30 inches of mercury, and this is equal to 
about 15 lbs. to the square inch, so we cannot err far in stating that for 
every inch of variation of the mercury in a barometer there is a diffe¬ 
rence of half a pound of pressure upon the square inch when we know 
that a column of mercury is supported by the atmosphere almost 
50 inches m height. This alteration of barometric pressure is not with¬ 
out its influence upon our fires, for on a cold frosty night this pressure 
is greater than during dull foggy weather ; therefore the gases are 
more compressed, more oxygen being contained in a given measure of 
air tnan when the pressure is less. Again, temperature materially affects 
the expansion and c ontraction of gases. One volume at 0° Centigrade 
would become 1'00366 for every 1° of rise of temperature. But if I put 
i is way I may be better understood. 273 volumes of gas at the 
normal temperature (0 ) and pressure (760 millimetres) will become 
“If V °i UmeS at , 1 -’ 27 & volumes at 2°, and so on, increasing a volume for 
every degree of rise of temperature, and vice versa. Now, we know that 
t hp th f e nigbt the greater will be the barometric pressure, and also 
th ? contraction of the gaseous envelope which surrounds 
the globe ; and these combined will enable our furnaces to obtain more 
n i.f an<1 much m °re too—from a given measure of air than they 
in btam fr0n ? the sanie mea sure when the temperature was high 
between f UPe leSS ‘ ®" tbesalcs thcse - the differences in temperature 
oetween the furnace and the external atmosphere will be oT ea ter during 
than ^en foggy, and this ^itself mS to caTs! 
• a material difference in the burning of the fuel, as it] will very sensibly 
Your correspondent, Mr. Burton, in your issue of the 27th inst., 
asserts that I admit a “failing in my system, which may to some 
extent account for the rusting of the bars.”' What this “ failing ” is he 
does not tell your readers—at least, I cannot grasp it, and am of opinion 
that it must be looked for in another quarter. He then endeavours to 
make us believe that only a small quantity of water is evaporated by a 
furnace. Had he stated the conditions— i.e., the size of the fire and its 
proximity to the water—all would have been right, but as this is not 
done the statement has a tendency to mislead those unacquainted with 
the facts. 
The furnace and ashpit with which I am about to deal were specially 
constructed for the purpose of supplying steam as a supporter of com¬ 
bustion, and better adapted for this purpose than those under the 
supervision of Mr. Burton, to judge them by his statement. The ashpit 
is a cast iron trough 4 feet 9 inches long, 1 foot wide, and 10 inches 
deep, but instead of this trough being entirely under the furnace, 
15 inches extends beyond the? front of it into the stokehole, and with 
the floor of which it is level. When this trough is full of water there 
is only a space of 1^ inch between the water and the fire bars. Now, 
as it is absolutely necessary to maintain a very high temperature in 
this furnace, and the amount of water evaporated by its influence is 
much at variance with what Mr. Burton says. In one hour the water 
in this ashpit was lowered 2 inches by evaporation, and had all the 
water been immediately under the furnace the quantity evaporated 
would most certainly have been very much greater. And all must 
know that the quantity of water dissipated by heat in a stated period 
depends wholly upon the amount of heat acting upon it. 
Mr. Burton is also a little “at sea” regarding the amount of vapour 
which a fire would “ attract.” The fire does not attract any vapour nor 
anything else, but the draught occasioned by the fire carries with it all 
gases and vapours within its neighbourhood, and those that are not 
utilised by the burning fuel pass unchanged through the fire and 
chimney to the external atmosphere. 
If Mr. Burton’s primary object in having water in his ashpits is to 
preserve the bars I regret to say that his efforts in that direction are 
entirely futile, as his theory is antagonistic to the natural laws observed 
in chemistry. And even although carbonised vapour may have 
the property of converting iron into steel, yet the steel is as susceptible 
of oxidation as it was before its conversion. 
But supposing for a moment that we laid aside these facts, which 
are all based on a sound chemical foundation, and accepted Mr. Burton’s 
idea that the main object of having water in ashpits was to keep the 
bars cool, we can easily see that he is in error, for it is at once apparent 
that the cooling of the bars would abstract a large amount of caloric 
power from the coal, and detract from instead of adding to the heating 
power of the furnace, thereby proving the false economical grounds 
upon which his ideas are based. — J. Riddell, Duncombe Park. 
[We have two other practical letters on this subject for which we 
regret our inability to find space this week. It will avoid confusion if 
correspondents await the appearance of those letters before sending 
further communications.] 
GRAPES SHANKING—ITS CAUSES AND REMEDY. 
Twelve years ago I took charge of a vinery planted with Black 
Hamburghs and Muscat of Alexandria, which looked very well at the 
time. The first thing I did was to thin and clip them, give them a 
thorough good watering, and wait for the result. When they began 
colouring I was very anxious, watching every day for the shanked 
berries, and I think I had to cut nearly half the berries out. After the 
Grapes werecut I examined the border, and at last I founda fewroots about 
18 inches long, so I took out all the exhausted soil from the inside of the 
house and put in fresh soil. The Vines were about forty years old ; a 
few roots ran into the outside border. Some of my gardening friends 
persuaded me to pull up the old Vines and plant young ones, but I was 
not my own master, and wanted a crop the next year, so I carefully laid 
out what few roots there were into the fresh soil and waited for the re¬ 
sult. Of course the Grapes shanked badly the next year, and my 
employer thought he had spent the money for no good purpose, but I 
desired him to wait till the next year. I carefully examined the Vine 
border, and found the roots 3 or 4 feet long in the new border. In the 
next year I found a great improvement in the Grapes, and gave copious 
supplies of water. I could see the roots working in the fresh border 
very fast, and I had but few shanked berries to clip out. The Vines 
began to improve very fast, and from that time I had very few shanked 
berries. I was induced by the account Mr. Taylor gave of his Vines to 
try the extension system on my Muscat, and the third rod which was 
taken up showed four bunches on every lateral, and ever since then has 
not seemed to have any vigour in it. This year I have determined to cu- 
it out. I have had some good bunches on the old rod. I cannot undert 
stand why the new rods do not grow as strongly as the first one. Accord¬ 
ing to Mr. Taylor the further they run the stronger they would be, but 
it is quite the reverse here. Black Hamburghs in the past showed signs 
oeakness, for I found several shanked berries to clip out that l o ok as 
