[119] 



Selecteb IRotes from tbc Society's 



mote*Booft0. 



Naphthaline is a white, flaky-looking crystal, which accumulates 

 in gas-pipes (to my great annoyance), gradually choking them up. 

 It can be procured at the gas-works when some of the periodical 

 cleaning takes place. 



Dissolved in mineral naptha and crystallised on a slide by eva- 

 poration, it forms an interesting object. I find difficulty in 

 mounting it. Castor-oil dissolves it instantly ; glycerine does so 

 slowly. 



Richard Smith. 



Naphthaline is described in " Chambers's Encyclopaedia " as 

 being easily and abundantly produced from the last portion of the 

 distillate of coal-tar," crystallising in large, thin, rhombic plates, 

 having a pearly lustre. 



R. H. Moore. 



Chalcedony. — I see little structural difference between Chalce- 

 dony arnd Siberian Agate, but am not surprised at this, as I learn 

 from Tomlinson's " Arts and Manufactures " that the chemical 

 composition of agate, chameleon, chalcedony, onyx, bloodstone, sard, 

 moss-agate, and many others, is identical. In the slide before us, 

 the discs are nearly perfect, and justify the old name, viz., 

 *' Fortification Agate." The Siberian agate is more wavy in 

 appearance, and the centre is broken up, as it were, by gritty- 

 looking particles, but is a more brilliant object under the polari- 

 scope. 



H. E. Freeman. 



We have certainly advanced since the days of Pignelius, 

 who remarks on Chalcedony, in connection with Rev. xxi. 19, 

 that the " stone hath the colour of a pallid lamp, shines in 

 the open air, but is dark in a house, carmot be ait (!), and has 

 powers of attraction." What would he have said to the section 

 before us ? 



E. E. Jarrett. 



