Areo'^neter. 118 



also have been unable to detect decided colour with any 

 telescope, beyond a ruddy tinge in one or two, certainly no 

 colour to compare even remotely with those of k Crucis. 

 And the magnitudes and positions of the stars around -q, as 

 seen in the Great Telescope, agree in most cases sufficiently 

 well to enable the discrepancies to be assigned to ordinary 

 errors of observation and reduction. Where any important 

 differences occur they are generally found among small stars, 

 which, although palpable enough in a four feet aperture, 

 must have been at the extreme limit of vision in Sir John's 

 18-inch reflector. 



It does not seem to have been before remarked of the 

 stars which are in optical connection with the nebula, that 

 they cluster most about those parts where the nebula is, or 

 has been, most condensed. This appears from Sir John 

 Herschel's drawing and catalogue as well as my own, and is 

 suggestive of physical connection between stars and nebula. 



Art. XXXIII. — Areometer. By George Foord, Esq. 



[Read 9th October, 1871.] 



The instrument which I have noAV the pleasure of sub- 

 mitting to your inspection involves no new principle, and 

 can scarcely lay claim to novelty of form ; it is in fact no 

 more than a modification or expansion of what has been 

 already described. I beg to remind you that occasionally 

 during the Society's meetings, when the papers read have 

 happened to make a somewhat short evening's sitting, it 

 has been felt that some light supplementary subject would 

 fulfil a want, by extending the business to a convenient 

 duration. It is in this sense that I now venture to place this 

 f )rm of areometer before you, premising that in Lehmann's 

 Physiological Chemistry, — the English edition, published by 

 the Cavendish Society, at page 437 of vol. ii. of that 

 work, occurs the following passage: — "Among the different 

 areometers there is only one which deserves any special 

 notice ; but this instrument, which is constructed by 

 Alexander, of Munich* yields, according to my experience, 

 much more accurate results than one might be disposed to 

 expect, a priori, from its construction. It is arranged in 

 the following manner : — ' two parallel graduated tubes, 



* Polytechn. Centralb., 1847, Heft 6, s. 361, 

 I 



