66 REPORT 1871. 



compounds ■will he explained by liimself in a lectiu-e with -wliicli lie tas kiudly 

 undertaken to favour the Association. Mr. Tomlinson -will also communicate to the 

 Section some observations on catharism and nuclei, a difficult subject, to which he 

 has of late devoted much attention ; and I am also informed that we shall have 

 important papers on recent improvements in chemical manufacture. 



No one can be more painfully alive than myself to the serious omissions in the 

 historical review I have now read, more particulai'ly in organic chemistiy, where 

 it was wholly impossible to grapple with the large number of valuable works 

 which even a few months produce. I cannot, however, refrain from bearing an 

 humble tribute to the great abilitj' and indomitable perseverance which characterize 

 the labourers in the gi'eat field of organic chemistry. It woidd scarcely be pos- 

 sible to conceive any work more intelligeutly undertaken or more conscientiously 

 performed than theirs, yet much of it, from its abstruse character, receiving little 

 sympathy or encouragement except from the band of devoted men who have made 

 this subject the chief piu^suit of theii* lives. They will, however, find their reward 

 in the consciousness that they have not lived in vain, but have been engaged, and 

 successftdly engaged, in the noble enterprise of extending for the benefit of the 

 human family the boundaries of scientific knowledge. Nor is there any real 

 gi-ound for discouragement. Faraday, Graham, Magnus, and Herschel, who have 

 left their impress on this age, were all distinguished chemical as well as physical 

 discoverers ; and the relations of the sciences are becoming every day so intimate 

 that the most special research leads often to results of wide and general interest. 

 No one felt this truth more clearly or illustrated it better in his writings than our 

 lamented and distinguished friend Dr. Miller, whose presence used to cheer our 

 meetings, and whose loss we all most sincerely deplore. 



Facts developed by the Worh'mg of Hceraatite Ores in the Ulverstone and White- 

 haven Districts from 1844-71. By Thomas Ainswohth. 



On the Dichroism of the Vapour of Iodine. By Dr. An'deews, F.R.S. 



The fine purple colom' of the vapour of iodine arises from its transmitting freely 

 the red and blue rays of the spectrum, while it absorbs nearly the whole of the 

 green rays. The transmitted light passes freely through a red copper or a blue 

 cobalt glass. But if the iodine vapour be sufiiciently dense, the whole of the red rays 

 are absorbed, and the transmitted rays are of a pure blue coloiu: ; they are now 

 freely transmitted, as before, by the cobalt glass, but will not pass through the red 

 glass. A solution of iodine in sulphide of carbon exhibits a similar dichroism, and 

 according to its density appears either pm-ple or blue when white light is trans- 

 mitted through it. The alcoholic solution, on the contrary, is of a red colour, and 

 does not exhibit any dichroism. 



On the Action of Heat on Bromine. By Dr. Andrews, F.B.S. 



If a fine tube is filled one half with liquid bromine and one half with the vapour 

 of bromine, and after being hermetically sealed is gi-aduaUy heated till the tempe- 

 rature is above the critical point, the whole of the bromine becomes quite opaque, 

 and the tube has the aspect of being filled with a dark i-ed and opaque resin. A 

 measure of the change of power of transmitting light in this case may be obtained 

 by varying the proportion of liquid and vapour in the tube. Even liquid bromine 

 transmits much less light wheu heated strongly in an hermetically sealed tube than 

 in its ordinary state, 



Some Memarhs ii2)on the Proximate Analysis of Saccharine Matters. 

 By Professor Apjohn, F,B,S, 



