194 
VENTILATION ON BOARD SHIP. 
suddenly into confinement and a vitiated atmosphere, must 
be exposed to many dangers, and the same thing is incurred 
on their leaving the ship. 
The windsails cannot always be depended upon, and at the 
best they are inconvenient, as they only partially clear out 
the hold ; and in many cases, by directing a current of cold 
air upon the backs of horses standing underneath them, 
colic is thus given rise to. In stormy weather, too, they arc 
useless, and in warm weather they are but little better, so 
that I think other means might be had recourse to, which 
would accomplish the desired purpose at a very little expense. 
Might not something in the shape of a pair of fanners, be 
placed in the hold, having a communication with one or two 
windsails above on the deck ; and which in those ships pro- 
pelled by steam, might have the necessary moving power 
given to them from the engine. What a benefit it is to the 
firemen in such ships to have a small leaf performing a back- 
ward and forward movement by means of the engine. A far 
greater one would accrue from the adoption of a similar prin- 
ciple in the holds where animals are kept, and the fanner 
could be provided with a hose by which the air could be 
forced into every nook and corner. Even in a sailing ship, 
one or two men, three or four times a day, turning the 
machine, would be sufficient to effect a change for the better; 
and this, conjoined with proper cleanliness, & c., would render 
the thorough ventilation of such vessels, in a manner, inde- 
pendent of windsails. 
The greater number of our disinfectants are of little use in 
such confined places, very often giving rise to odours nearly 
as prejudicial to health as those they are intended to destroy 
or alter ; still I think that the more general adoption of the 
freshly prepared hydrate of lime, so much recommended by 
Liebig in his letters, would have a greater tendency to do 
good, by robbing the air of the carbonic acid, for which it 
has such a powerful affinity, is to be advised. The only 
thing to be said against its use is, that it gives off a large 
amount of watery vapour during its chemical combination, 
but this objection does not weigh much in comparison with 
its other good qualities. Three or four sievefuls placed in 
different parts of the ship would almost suffice for twenty-four 
hours, provided it was frequently stirred up. 
