6g8 PHILOSOPHICAL TRANSACTIONS. [anNO l/Qt). 



metrical mensurations, and calculations founded on them, and observations be 

 made on the performance of these vessels at sea ; experiments of this kind suffi- 

 ciently diversified and extended, seem to be the proper grounds on which theory 

 may be effectually applied in developing and reducing to system those intricate, 

 subtile, and hitherto unperceived causes, which contribute to impart the greatest 

 degree of excellence to vessels of every species and description. Since naval 

 architecture is reckoned among the practical branches of science, every voyage may 

 be considered as an experiment, or rather as a series of experiments, from which 

 useful truths are to be inferred towards perfecting the art of constructing vessels: 

 but inferences of this kind, consistently with the preceding remark, cannot well 

 be obtained, except by acquiring a perfect knowledge of all the proportions and 

 dimensions of each part of the ship ; and '2dly, by making and recording suffici- 

 ently numerous observations on the qualities of the vessel, in all the varieties of 

 situation to which a ship is usually liable in the practice of navigation. 



FI. The Discovery of a New Comet. By Miss Caroline Herschel. p. 131. 



Last night, (Nov. 7, 1795), in sweeping over a part of the heavens with my 

 B-feet reflector, I met with a telescopic comet. To point out its situation I refer 

 to my brother's observations on it from his journal. 



From these observations it appears that the direction of the comet's motion 

 seems to be towards the south preceding side, and it is about 5 or 6' removed 

 fi-om its former place, in the time of about 1 hour. The diameter of the comet 

 is about 5'. It has no kind of nucleus, and has the appearance of an ill-defined 

 haziness, which is rather strongest about the middle. It will probably pass be- 

 tween the head of the Swan and the constellation of the Lyre, in its descent to- 

 wards the sun. The direction of its motion is retrograde. 



Place of the comet deduced from the observations. 



Nov. T . .0^ 33'" RA . . 20'> 3'" 48' pd . . 49° J 7' 18" 



. . 3 37 20 O 58 49 37 18 



Additional Observations on the Comet. By IVm. Herschel, LL.D, F.R.S. 



p. 133. 



Nov. 8, 2'^ •27"'. The comet is 36' from 22 Cygni ; its motion has been very 

 nearly in the line pointed out before. It will however not pass over 22, but go 

 by it towards 19 Cygni, having left the line pointed out, a little on the follow- 

 ing side. 



Nov. 9, 20'' 45"*. The comet is 1 7 or 18' from 15 Cygni. 



At 21 59 . The comet is centrally on a small star north following 15 



Cygni. It is a small telescopic star of about the 11th or Tith magnitude, and 



