REMARKS ON WOOD AND METAL. 
725 
gard to 1]is friend’s observation :—that it answers better for peaches 
than nectarines, it is utterly unfounded, being completely at variance 
with our observations: we find little or no difficulty with any except 
weak trees of some of the white peaches, which are thin of wood-buds; 
but this is very seldom the case with nectarines. 
Wm. Seymour. 
Palace Gardens, Bishopsthorp, near York,) 
August 13///, 1832. £ 
ARTICLE IV. 
COMPARATIVE REMARKS ON WOOD AND METAL, AS 
CONDUCTORS OF HEAT. 
BY MU. CUR. 
As “Epliebicus Horticultor,” has with some warmth, criticised a letter 
I wrote in behalf of metallic hot-houses; I consider it requisite to 
make some reply, in defence of what I there advanced. Mr. E. H. 
says, I ascertained, that metal and wood were equal conductors of 
heat, if kept well painted; what I meant was, that wood and metal 
are equal conductors of the heat of the sun, or of our atmosphere, 
and not of water and sand, &c. Mr. E. H. appearing to have a 
pretty competent knowledge of the properties of Caloric, must be 
aware of the difference of its conduction in one element, to that of 
another; were he to take equal sized rods of metal and wood, both 
being well painted, and half covered with wax, as directed by him¬ 
self, page 583, and place them in the sun-shine in an erect position, 
he would soon see the equalisation of the conduction of Caloric, for 
the wax on the wood would melt equally as soon as that on the me¬ 
tal, and I conceive this to be the more proper way of trying an 
experiment with regard to hot-houses, for the rafters are never 
immersed in water or sand. Mr. E. H. says, “when I placed the 
pieces of wood and iron against the south wall, I made my observa¬ 
tions on the same side I applied the heat, and if I had felt the op¬ 
posite side, I should have found a great difference; this is asserted 
with as much assurance as though he had been present. Now I can 
assure him, I felt on both sides, and found no difference ; I am also 
in the habit of examining wood and metal rafters every day, (half of 
my houses being constructed of metal,) and were there any material 
difference, I could not fail to have observed it. My pines were ne- 
