180 



and satiny lustre, sparingly soluble in water, ai-d in cold alcohol, 

 but much more so in boiling dilute spirit, from which it is deposited 

 on cooling, and insoluble in ether. It dissolves in alkalies with a 

 fine red, and in sulphuric acid with a violet colour, and is decom- 

 posed by heat with the production of a ci'ystalline sublimate. The 

 analysis gave the following results : — 



Carbon, . 55-46 55-40 55-39 



Hydrogen, . 5-19 5-03 



Oxygen, . 39-35 39-57 



100-00 100-00 



From which the author deduces the formula C^g H15 0^5, which 

 differs from that of sublimed madder purple, the probable formula of 

 which is C28 Hjg O^g, by a single equivalent of water only. It 

 approaches very closely in many chemical characters to the madder 

 colouring matters, but differs from them in its relations as a dye. 

 For the author had found that it was incapable of producing colours 

 with alum and iron mordants, but with turkey-red mordant it pro- 

 duces a dark red. 



By the sublimation of morindine, the author obtained another 

 substance, to which he gives the name of morindone, in the form of 

 fine red needles of considerable length, and which is insoluble in 

 water, both hot and cold, but soluble in alcohol and ether. It dis- 

 solves also in alkalies with a magnificent purple colour, and in strong 

 sulphuric acid, with the same colour. The author had been able 

 to make only an imperfect analysis of this substance, the results of 

 which approximated to the formula C^g Hiy O^,,, and should this be 

 confirmed, would differ only from madder red by a single equivalent 

 of water, and be a polymeric of gentianine. 



The author concluded by remarking that morindine formed the 

 type of a new class of colouring matters, fixing only on turkey-red 

 mordant, which would, in all probability, throw some light on the 

 obscure subject of the theory of tui'key-red dyeing. 



3. An Attempt to improve the present Methods of determin- 

 ing the Strength and Direction of the Wind at Sea. By 

 Professor C. P. Smyth. 



The laxity of the present methods having been brought, by his 

 friend Captain Cockburn, R.N., before the author, with a desire to 



