XVI 



In 1841 Kane received the Royal Medal of this Society for his 

 work published in the ' Philosophical Transactions ' for 1840 on the 

 chemical history of the well-known substances archil and litmus, 

 which are colouring matters obtained from various lichens of the 

 Bocella, Variolaria, and other genera. When the lichens are allowed 

 to ferment in presence of ammoniacal salts, they soon afford the 

 magnificent purple-red colouring matter termed orceine. But if 

 carbonates of the alkalies are present during the process of fermenta- 

 tion, blue litmus results. The two colouring matters were previously 

 examined by Robiquet, Heeren, and Dumas, yet Kane carried the 

 investigation much further, and not only improved the methods of 

 separating some of the substances present in the impure pigments, 

 but endeavoured to trace them to proximate constituents of certain 

 of the lichens. In the course of this laborious investigation he 

 obtained a number of new substances which he regarded as definite 

 compounds. The general result of the inquiry was that the red 

 " orceine " of archil, and the blue substance of litmus, named by 

 Kane " azolitmin," differ only by one atom of oxygen, the blue 

 coloured body containing most oxygen ; and that both colouring 

 matters are products of the action of ammonia and atmospheric air, 

 in presence of a ferment, on orcin already free in the lichens or 

 resulting from the hydrolysis of some of their constituents. 



In 1842 Kane published an account of his examination of the 

 colouring matter of the berries of Bhamnus tinctoria, one of the 

 buckthorns, which were imported in considerable quantities from the 

 Levant for dyeing, under the name of " Persian berries." From 

 these when in the unripe state he isolated a golden-yellow colouring 

 matter, which he named chrysorJiamnine, and from the ripe berries, 

 olive-yellow xanthorhamnine, and showed that the latter results 

 from the action of oxygen and the elements of water on chryso- 

 rha amine. 



Plant products always seemed to have a great attraction for Kane, 

 and amongst others the volatile oils, with which he worked much 

 from time to time, though he published little about them, as he found 

 greater difficulty than he anticipated in arriving at a " law connecting 

 the composition of the secretions of plants of the same genus or 

 natural family." But he made some useful contributions to our 

 knowledge of these oils, as well as to that of other minor subjects, 

 which the limits of this notice do not permit us to specify in detail. 



In 1843 Kane was appointed Professor of Natural Philosophy to 

 the Royal Dublin Society, and during the following year published 

 his ' Elements of Chemistry,' a work which well represented the 

 general theories and the practice of the science at the time. But his 

 connexion with the Royal Dublin Society — a body which has always 

 been foremost in seeking to develop agriculture and industry in 



