Mr. J. R. Napier on Sliips' Compasses. 365 



" Mr. Walter Crura, of Thornliebank ; Dr. Thomas Anderson ; Prof. 

 TV. Thomson ; Mr. J. E. Napier ; Mr. W. Gale ; Mr. Neil Eobson ; Mr. 

 James Thomson, C.E., Belfast ; Mr. W. Gardner ; Mr. Paul Cameron ; 

 Mr. Alexander Mitchell ; Mr. D. Mackain ; Dr. John Macadam ; Mr. 

 Thomas R. Gardner ; Mr. James King ; Mr. Hughes ; Mr. Robert Hart, 

 Govan ; Mr. John Finlay, 46 Buchanan Street ; Mr. Malcolm M'Neill 

 Walker, 24 Clyde Place ; Dr. Strang ; Professor Eadie ; Mr. Simpson ; 

 the other Members of Council of the Society not named in the above 

 list; Mr. W. J. Macquorn Rankine, Convener." 



Mr. Hart described two luminous spots he had recently observed on 

 the Moon's disc. 



The President read a paper " On some Recent Discoveries with re- 

 spect to the Impregnation of the Ovum in Fishes and other animals." 



Mr. James R. Napier read " Remarks on Ships' Compasses," and was 

 requested by the Society to recapitulate his paper at next meeting, in 

 order to its being discussed on that occasion. 



January 24, 1855. — The President in the Chair. 



The following gentlemen were elected members : — Mr. William Neil- 

 son, Insurance Agent, 69 Glassford Street ; Mr. James King, Hurlet and 

 Campsie Alum Co., Glasgow ; Mr. Thomas Henderson, Merchant, 45 

 Union Street; Mr. James Greenshields, Chemist, 110 Peel Terrace. 



Mr. Rankine reported the progress of the Committee on Philosophical 

 Instruments for the Paris Industrial Exhibition. 



Mr. Hart produced a letter from the Astronomer Royal, stating that 

 he had no doubt that one of the spots observed on the moon by Mr. 

 Hart was an occulted star. As to the other, it was in a region of the 

 moon which the Astronomer Royal had often studied as an amateur, but 

 he had never seen the phenomenon described. 



Remarks on Ships' Compasses. By James R. Napiek. 



It will be admitted by most persons, that all other things being equal, 

 the best compass is that which has the strongest magnetism in its 

 needles, or the most directive power in proportion to the whole weight of 

 card and needles ; for, by having this superior directive power, it is en- 

 abled to overcome pivot friction and other causes, which render useless 

 less powerful compasses. 



Compass makers evidently aim at developing in their needles as much 

 magnetism as possible, and Dr. Scorcsby's principle of making them hard 

 in order to retain this development is, I believe, generally admitted and 

 adopted. I conceived, therefore, that after the numerous experiments 



