72 REPORT — 1876. 



In order to purify aconitine completely from another base which does not crystal- 

 lize from ether, but which obstinately adheres to aconitine when crystallized from 

 that and other menstrua, it is sufficient to dissolve the approximately pure snow- 

 white crystals already crystallized several times from ether in warm dilute hydro- 

 bromic acid ; on cooling and standing, well-defined crystals of the hydrobromide of 

 aconitine separate, the other base being completely retained in the mother liquors ; 

 the drained and washed crystals yield perfectly pure aconitine on dissolving in water, 

 precipitating by sodium carbonate, and crystallizing the precipitate from ether. 

 This non-crystalline base does not appear to form crystallizabie salts ; it has a 

 considerably lower molecular weight than aconitine. Whether it is originally 

 present in the roots, or is formed by alteration of the crystallizabie aconitine during 

 the extraction process, is not yet made out. 



These results, and those obtained last year, clearly point to the desirability of sub- 

 stituting for medicinal purposes the uniform homogeneous crystallized base (or a 

 salt thereof) for the more or less amorphous mixtures of aconitine and other sub- 

 stances and alteration products usually found in pharmacy, inasmuch as some at 

 least of these admixtures are considerably less physiologically potent than aconitine, 

 C33H43NO12. 



Further experiments on the constitution of aconitine and the amorphous base or 

 bases are in progress. 



GEOLOGY. 



Address by Professor J. Young, M.D., F.G.S., President of the Section. 



When the British Association met in Glasgow twenty-one years ago, Sir Roderick 

 Murchison presided over Section C, and was surrounded by a brilliant company, 

 whose names, now historical, were even then familiar for their accuracy of observa- 

 tion, for philosophic generalization, and for the eloquence with which'theii- science 

 was clothed in words that charmed while they instructed — Lyell, Hugh Miller, 

 Sedgwick, Jukes, Smith of Jordan Hill, Thomas Graham, Agassiz, Salter, Leonard 

 Horner, John Phillips, Robert Chambers, H. D. Rogers, Charles Maclaren, Sir W. 

 Logan : the list is a heavy one even for twenty-one years ; and the changed cir- 

 cumstances will be fully realized by Nicol, Harkness, Egerton, Darwin, Ramsay, 

 and others when they find Murchison's place occupied by one who holds it rather 

 by the courtesy of the Council to the Institution in which we are assembled than 

 by any claim he has to the honour. 



It would be out of place for me to do more than refer to the Geological advantages 

 which have given to Glasgow its commercial greatness. In the Handbook prepared 

 at the instance of the Local Committee will be found gathered together all the 

 positive knowledge we possess regarding the mineralogy, stratigraphy, and palaeon- 

 tology of the west of Scotland. The specimens themselves are exhibited in the 

 Hunterian Museum and in the Corporation Galleries ; and I take it upon me to say 

 the Glasgow geologists are as ready as ever to assist the investigations of students 

 in special departments with all the material which richly fossiliferous strata yield 

 and the careful skill of assiduous collectors can secure. 



Thus relieved from entering into local details, 1 would ask your attention for a 

 short while to some of the difficulties which a teacher experiences in summarizing 

 the principles of Geology for his students. 



I may be pardoned for reminding you that as yet there are in Scotland only two 

 specially endowed teachers of Geology. In the iCniversities, that science for which 

 Scotsmen had done so much received only the odd hours spared from Zoology. In 

 1867 the two courses were separated in Glasgow ; in 1870 Sir R. I. Murchison 

 founded the Chair of Geology in Edinburgh ; in 187C ]\Ir. Honyman Gillespie 

 endowed a Lectureship on Geology in Glasgow, not separating it from Zoology, but 

 rather desiring the two to remain associated, while means were provided for tutorial 

 instruction in the elementary work of the class. When next the Association meets 



