( 4 10 ) 
H perienced Perfon, {landing at the foremoft Mark, 
u throws a Chip over-board, and counts the feveral 
44 Beats of his Pulfe, during the Chip’s Pallage from 
44 one Mark to the other j and from thence it is they 
a compute the Number of Miles that the Ship runs 
44 in an Hour. 
44 As for the Marine-Surveyor, it is not hove with 
u a Line, but is tow’d a Stern by a Rope; and let 
41 that Rope {{retch or (brink (be long or ihort) it is 
44 all one, for the inftrument will have the fame true 
“ Revolutions. Should it be objected, that it holds 
Water, 1 affirm, from my own Experiments of it, 
4 that the Log haul'd in from 5 or 6 Knots, is much 
44 heavier upon the Hand } and that the fafler the 
44 Ship runs, the lefs Water this Inllrument of mine 
‘ holds, becaufe it gives Way to the Water and turns 
44 quicker ^ nay, 1 can venture to fay, that it is fo far 
44 from being any confiderable Impediment to the 
44 Ship’s Way that (lie does not lofe one Mile in an 
* hundred by it. But (hould this Inllrument be intro- 
44 duced into the Navy, in cafe of chafing an Enemy, 
44 or the like, it may be taken in at any l ime, and 
44 let down again at Pleafure. 
4. 4 I appeal to all Seamen, if in a moderate Gale, 
44 when the Ship runs 5 or 6 Knots, two diffe- 
44 rent Perfons (every way qualified) were to heave 
44 the Log immediately after one another, whether 
ct they would exadly agree. Surely no. Since his 
44 but Chance if they do fo, and is what may not 
44 happen in an hundred Trials. 1 therefore affirm 
44 the Log to be very erroneous on this Account, and 
44 that the Error frequently increafes with the Wind ^ 
for in a ftiff Gale, when a Ship has run about 8 or 
“ 9 Knots before the Wind, it has been known that 
44 two expert Seamen have hove the Log in this Man- 
