114 Gibbs on Dry Roi. 
alternately close in with one pia or the other, as their winding 
course directs the force of the current. A steam — therefore 
which has no external wheels or ene ey will be less exposed to 
accidents from the shore, the trees upon it, or from drift wood. 
FOR THE AMERICAN JOURNAL OF SCIENCE. 
Arr. XI. Observations on the Dry Rot, by Col. Gzorce 
, ees: , , ‘ 
Tur Jate extraordinary debsy of Pitnbér, by a disease, 
termed the dry rot, in the commercial and military marine © 
in Europe, has excited much attention, and called forth ma- 
ny schemes for prevention or cure. But I have not been 
fortunate enough to meet with any account of its cause, or 
any proposal for a remedy, which could satisfy me, still less 
e Gentlemen skilled in naval affairs. 
It appears, karat — disease affects w ood, whether dry of 
moist, though more in the latter case : "aoe t has become 
more common within go years, and since tint time large 
ships have been discovered to be entirely rotten on the 
then” before the preparations were made for launching 
t 
‘Steaming the Timber has been tried in America, and 
Seed 3 injurious ; oil and paint are ruinous; and many oth- 
er operations have been recommended, some of which were 
found i injurious, others ineffectual, others too costly for tri- 
al. All the ingenuity of the English mechanics seems ta 
_ have been employed in scheeming and failing; much mo-- 
ney, and. some lives, have been lost i in these ore sory : 
‘Rot has been ascribed to the use of green 
bans wood not sufficiently seasoned or docked ; ‘bat, ; 
docking timber is, to a considerable extent, impor- 
tant, yet it is found that this remedy is by no means sure, 
as ships with which this precaution, as formerly, has pe 
tried, have. been found at times subject to the dry rot; 
that in spite of every oe large vessels in Europe do bik 
last half as long as for 
In the United States this gieeacee is by no means as com- 
mon, although it sragually becomes more so. Our mer- 
ee TF 
