MARITIME OBSERVATIONS. 317 
‘be very ufeful; and a veflel from America to Europe may 
do the fame by the fame means of keeping in it. It may 
have often happened accidentally, that voyages have been 
fhortened by thefe circumftances. It is well to have the 
command of them. 
But may there not be another caufe, independent of 
winds and currents, why paflages are generally fhorter 
from America to Europe than from Europe to America ? 
This queftion I formerly confidered in the following fhort 
paper. 
ie On board the Pennfylvania Packet, Capt. Ofborne, 
At fea, April 5, 1775. 
“ Suppofe a fhip to make a voyage eaftward from a 
place in lat..40° north, toa place in lat. 50° north, diftance 
in longitude 75 degrees. 
« In failing from go to 50, fhe goes from a place where 
a degree of longitude is about eight miles greater than in 
the place fhe is going to. A degree is equal to four mi- 
nutes of time; confequently the fhip in the harbour fhe 
leaves, partaking of the diurnal motion of the earth, moves 
two miles in a minute fafter, than when in the port fhe 
is going to; which is 120 miles in an hour. 
«¢ This motion in a fhip and cargo is of great force; and 
if fhe could be lifted up fuddenly from the harbour in 
which fhe lay quiet, and fet down inftantly in the latitude 
of the port fhe was bound to, though in a calm, that force 
contained in her would make her run a great way at a 
prodigious rate. This force muft be loft gradually in her 
voyage, by gradual impulfe againft the water, and proba- 
bly thence fhorten the voyage. Query, In returning does 
the contrary happen, and is her voyage thereby retarded 
and lengthened ?”’ * 
Would it not be a more fecure method of planking fhips, 
if inftead of thick fingle planks laid horizontally, we were 
SS) to 
* Since this paper was read at the Society, an ingenious member, Mr. Patterfon, has con- 
vinced the writer that the returning voyage would not, from this caufe, be retarded. 
