94. 



APPENDIX. 



the line marked fifty-one feet to thirty feconds, one degree 

 fifty-eight minutes aftern of the fliip, with the Hne marked 

 forty-five feet to thirty feconds, four miles ahead of the 

 Ihip. On the paflage home, the log at fifty-one feet to 

 thirty feconds, thirty-five miles aftern of the {hip ; at 

 forty-five to thirty feconds, one degree feven minutes 

 ahead of the Ihip. As far therefore as the experience of 

 this voyage extends, it appears that the errors of the log 

 marked forty- five feet are always on the fafe fide, and that 

 thofe of the longer marked line are always fhort of the 

 run; but that Bouguer's is much more accurate than 

 either. 



It is not to be expeded that the obfervations of a fingle 

 voyage can be fufiicient to determine the merit of any in- 

 frrument, particularly one of fo much confequence as the 

 log. I thought it right, however, to give an account of 

 the trial I made of the different methods, and of fuch 

 remarks as occurred to me. 



In the following table the courfe is put down, in the 

 firft column, for all the diftances and latitudes ; after the 

 diftance and latitude, according to each marking of the 

 log, there is a column for the difi'erence between that la- 

 titude, and the latitude obferved. I thought it beft to 

 continue the reckonings without corredions, as if there 

 had been no obfervation, in order to iliew the difference 

 upon the whole run, as well as from one obfervation 

 to aiiother. 



TABLE. 



