Dr John Davy on the Production of Mist. Ty 
I need hardly advert to the vulgar opinion, that the moisture 
in question is an exudation from the stone itself—a belief 
implied in the term “ sweating,” used to express it. 
This precipitation of moisture and production of mist are 
most conspicuous in such situations as are exposed to great 
and sudden transitions of temperature, such as Constantinople 
situated between the Black Sea and the Mediterranean ; the 
towns on the shores of the Adriatic, especially of its upper 
portion; the islands of the Mediterranean most exposed to 
the warm and damp sirocco, such as Malta; and in England, 
the towns on the south-west coast of Dorset and Devon. 
A dread of it amongst the inhabitants of Constantinople 
has led them to give the preference to wooden houses, notwith- 
standing the constant danger of destruction from fire to which 
they are exposed, and from which they have so often suffered. 
Stone houses they consider unwholesome ; and to a people such 
as the Turks, trusting chiefly to clothing for protection from 
the cold of winter, they can hardly be otherwise. In England, 
it is to feared, that amongst the poorer class, who cannot afford 
to keep their dwellings warm by fires, their health may suffer 
from this cause.* And, granting this, does it not follow, that 
the natives of the wilder parts of Scotland, the Highlands and 
Isles, and of the similar parts of Ireland, have reason on their 
side in keeping to their warm turf-built huts, preferring them 
to the cold stone-built slated houses ? 
Not only in relation to health and comfort is the subject of 
interest ; it is hardly less so in relation to the well-keeping of 
objects which are liable to suffer from damp. And how few are 
there which are not! Moisture, which is essential to vitality, 
is, as 1s well-known, equally essential to decay. In Upper 
Egypt, the climate of which is so remarkable for its dryness, 
works of art are perdurable. In our moist climate, how great 
is the contrast; how few of our stately buildings, even though 
* The health of prisoners is endangered from the same cause, when their 
sleeping cells, of massive masonry, are detached from the main building with- 
out the means of being warmed. This last winter, in a county house of correc- 
tion, I have been informed that the inner walls of some of the cells were not 
only wet from precipitated moisture, but were in the morning actua!ly covered 
with ice, the breath of their inmates corresponding in quality to the moist aad 
Warm sirocco. : 
NEW SERIES.—VOL, XIV. NO. I.—JuLY 1861. c 
