Queries, Answers, liemarks, S^c. 135 
to you at the pits, I have put this canal here, in order to counteract any evil 
eftecls that might occur from the flues heing accidentally over-heated, and also 
to give out a regular moisture in proportion to the fire used; which it does to 
so great a nicety, that the leaves of plants, instead of being exhausted, (as is ge 
nerally the case,) after a severe frost, have a healthy dew-drop hanging upon 
them. When the fruit is ripening, or moisture is not necessary, the water in 
the canal is discontinued. 
Q. — How much might this range of houses cost? 
A. — I will inform you. When I first contemplated erecting this range, I was de- 
sirous to know how much they would cost if erected of tneta!, having some 
notion of constructing them of it. I accordingly sent a plan to Birminghami 
and another to Sheffield, desiring to he furnished with estimates for the purpose. 
That from Birmingham was £ 1 800, and the other from Sheffield, £ 1850. This 
appeared to me an enormous sum ; 1 therefore set about calculating how much 
it would cost if made of wood, under my own eye •, and what do you imagine 
was the result? Why, 1 completed the whole range, including masonry, which 
was omitted in the metal estimates, for less than £500 ! ! ! 
After this explanation, I hope, Sir, you will never advance one word more as 
to comparison in the expense between wood and metal. Had I erected a hot- 
water apparatus, £200 more would have been necessary. To put up much of 
this in large (iardens, similar to Chatsworth, (even allowing it to be the best 
mode of heating) would be the height of extravagance, as numbers of our for- 
cing houses, are not heated artificially, above six weeks or two months in the 
year; and even some not so much as that, and then requiring but little fire. 
Now to have hot-water in such houses as these, also in greenhouses, when, in 
some seasons, not a fortnight's fire is necessary, would, as before stated, be the 
height of extravagance; the money necessary to bwy a hot-water apparatus for 
such a purpose, would supply the house with fuel for twenty years. 
Q. — Do you think these houses will last as long as if they were constructed of 
metal ? 
A . — It is impossible for me to give you a decided answer to that inquiry ; but from 
what I have seen of both, I will give you my opinion. — These houses are con- 
structed of the best materials, and from the impossibility of water ever being 
able to penetrate the sash-bars, there is every reason to believe they will keep 
good for a century, or more, if properly attended to. Metal is so recent an in- 
vention, that I am not able to say. how long a well painted house might last; but 
when they are the least neglected, I have observed them speedily perish : for 
instance, — the wrought-iron houses at Ham Hall, are fast going to decay, al- 
though they have been built only thirteen years; they are so much corroded as 
to be irrecoverably lost, and this has arisen from a trifling neglect in painting. 
You called there on your tour, I believe, and most likely noticed what I have 
stated. 
Q. — Of what materials then, would you construct large ornamental houses for 
plants, such as those at Syon, Bretton Ha'.l, &c. 
\. — Metal certainly, baton no account, if possible to be avoided, would I place 
them directly south, but it will take up too much of your time now, to go a 
length into this subject ; sometime when you call again, and have more leisure 
I will give you my opinion further on that point. 
Q. — Your forcing houses are not large, if tl.ey were, you must have had siroDger 
rafters, which would have darkened the houses considerably. 
A. — In that case I should have used cast-iron rafters ; let me here inform you 
that if iron of any description, receive two good coats of red lend ajl over, her 
