NATURAL HISTORY SOCIETY. 393 



of Arts, containing a proposal to mix tlie liquid with superphos- 

 phate of lime before distributing it, by which he considers that the 

 value of the constituent already contained in the liquid will be prac- 

 tically increased. It is, however, not likely that the opinion of a 

 chemist will decide the authorities to adopt an experimental scheme 

 of the kind, as it is really rather an engineering and commercial than 

 a chemical question. The practical test of value commercially is 

 how much an article will fetch ; and the data of this kind before 

 us do not lead to the anticipation of a profit at all approaching to 

 what theory suggests from the sale of this refuse. At Croydon (a 

 town of about 18,000 inhabitants) it appears that the sewage is sold 

 for something over a thousand pounds per annum. Another refuse 

 material which has already come to possess great value is coal tar. 

 Not only is our chief supply of ammonia, the food of plants, derived 

 from that source, but those brilliant and varied colours, which are 

 now so much in use for dyeing silk, also owe their origin indirectly 

 to the same source. There is, perhaps, no more striking instance 

 of the benefits which ultimately arise even to the manufacturing 

 arts, from every complete investigation of chemical substances than 

 is afforded by those beautiful dyes which have sprung up to-day 

 from aniline, which yesterday was a chemical novelty in the hands 

 of a first rate investigator." 



NATURAL HISTORY. 



THIRD REPORT OF THE SCIENTIFIC CURATOR. 



Since the annual meeting of the Society on May 19th, 1863, 

 from which this report dates, the annual report for the last season 

 has been issued to the members. Last year the published list of 

 members was very inaceurate, and special care has been taken to 

 remedy this defect. The list of donations to the museum during 

 the past year has been prepared very carefully, and the proper 

 scientific name of each specimen has been recorded. 



The co-operation of members of the Society is requested, in the 

 endeavour to make the annual reports in future as reliable as pos- 

 sible. The compiler will be thankful for the correction of any 

 error, or for the rectification of any omission — more especially in 

 the list of members. 



In consideration of Sir W. Logan's valuable donation to the 

 Society of marine shells, sea urchins, crustaceans, corallines, <fec, 

 (collected mostly in the Gulf of the St. Lawrence, by the officers 

 Can. Nat. 26 Yol. YIII. 



