52 
Evil Effects of Metallic Hot-houses. 
It is affirmed that the extra expense of Metallic Hot-houses is trifling, 
which I beg leave to deny ; there were two Hot-houses erected lately in 
this neighbourhood, belonging to Sir Clifford Constable, Bart. Tixall 
Hall; the one of metal, the other wood, in the usual way, of nearly equal 
dimensions, the latter rather the largest.—I am authorized to state that 
the expense of the metal house, amounted to double that of the wood 
one. This extra expense cannot surely be considered as trifling. About 
ten years ago, there were two pine-pits built in Shugborough Gardens, 
the rafters, and all but the frame of the sashes of metal, the price of 
which was 4s.6d. per superficial foot; and I am enabled to state, that if 
the work had been of wood, it would have been done for 2s. per foot— 
so much for the trifling extra expense of metallic structures. I next 
proceed to my experience of the durability and utility of the system in 
the forcing department.—With regard to the durability of it, I must ob¬ 
serve, that the following communication may not be considered as deci¬ 
sive in that respect, as the Houses were not entirely of metal, as is the 
present system, the bars of the sashes only being of that material; how¬ 
ever the builder did not fail to represent at the time, that it would be 
little short of everlasting. 
There wei*e three pine stoves, two peach, and two fig-hoUses, erected 
here about twenty-six years ago, the bars of the sashes being of metal. 
The two peach-houses lasted only sixteen years, two of the pine-stoves 
eighteen, when it was found necessary, from the shattered condition of 
the sashes, (the metal-work having given way,) to have them replaced 
with wooden ones. The remaining stove and fig-houses are still in use, 
but in so dilapidated a state, that they will not last above four or five 
years longer, at the utmost. With regard to utility, I am decidedly of 
opinion that it is no improvement. Although the Hot-houses under my 
charge were less liable to injury from the excessive heat which entire 
metal Houses are so subject to, yet in very hot summers I have found consi¬ 
derable inconvenience therefrom. Where the rafters and all are of metal, 
let not the foliage come in contact with them, if it does, it will inevitably 
be scorched, which must be very injurious to the fruit. In the summer of 
1818, which was very warm, my pine plants in the pits suffered consi¬ 
derably, before I was aware of the injurious effects of the excessive heat 
in those smaller compartments, it changed the colour of the leaves to a 
sickly yellow hue, and I have no doubt but that the swelling of the fruit 
was considerably deteriorated in consequence. The only means I had of 
preventing such baneful effects in future, was by shading the pits, and 
keeping the interior flooded with water. If the metal in summer attracts 
the heat to so hurtful a degree, it is equally attractive of frost in the win¬ 
ter, and it will be found that it is not at all calculated for early forcing. 
I hope you will not mistake me so far as to imagine the opposition I 
feel myself bound to make to this modern invention, is the effect of any 
