15 



lions eaiisod by the oooan, by volcanoes, &c. were enquited 

 into. The order of the superposition of the prinutive strata 

 was next shewn, and their peculiar curvetures described by 

 sketches tending to elucidate the subject. Selections were 

 made from the mineral cases in the Museum, that rendered 

 the substances spoken of familiar, and their constituents were 

 explained. The Lecturer offered an opinion that the primitive 

 mountains were forced up into their present forms by chemical 

 ag-ency alone, since the ultimate bases of their constituents 

 proved that they were nearly all composed of substances, 

 that with a moist air and low tempeiature were capable 

 of spontaneous ignition. He stated ihat granite which now 

 forms the loftiest peaks in the world, appears once to have 

 occupied the lowest levels,— that porphyry, clay-slate, and 

 primitive limestone were upheaved and flung into their present 

 vertical position, by its protrusion, and that prior to that ca- 

 tastrophe, observation and reasoning alike prove those sub- 

 stances to have been nearly level, and arranged merely as 

 coalings round the Earth's surface. 



Febrmiry 2. — The Rev. H. Lacey delivered a second Lec- 

 ture on tiie Hibernation of Animals. He remarked that the 

 first purpose of Hibernation, and which he treated of in a 

 fiirnicr Lecture, had repose for its object; and that in this he 

 should call attention to three other purposes of Hibernation — 

 dress, climate, and food. Under the first head he noticed 

 the changes which t^ike place in clothing during the hiberna- 

 tion of animals, sh(!wing them to be according to the consti- 

 tution and temperament of different animals, and adapted to 

 their manners, habits, and abodes, and to their geographical 

 situation. lie also noticed the general and partial changes in 

 colour and plumage of thi> feathered tribe, and the influence 

 of temperature in efl'ectiug these changes, observing that in 

 summer the plumage; was rich and vivid, in winter obscure and 

 dull ; and that these circumstances had led into error some of 

 our most distinguished ornithologists. He then stated his 

 opinion as to the manner in which t!ie changes in clothing and 

 plumage were effected,— and which he attributed to the dif- 

 ferences in the colour of secretions, and their diminution or 

 suspension, and ru>tic('d th(^ hypothetical reasoning of some 

 naturahsts on this subject. The Lecturer then hastily enume- 

 rated some of the migrating animals and birds, and called 

 attention t(» the wonderful phenomenon of the migration (»f 

 the latter, particularising those which hil)ernate in this country, 

 and iutiniatcil that gentlenn-n who had leisure might be pro- 

 fitably and usefully emphiyedin th(< elucidation of this doubt- 

 ful and uncertain branch of natural history. The Lecturer 

 jfave some observations on hibernation for the purpose of pro- 



