ANNIVERSARY ADDRESS. 7 



extended to — Systematic or descriptive chemistry; systematic 

 studies of chain molecules, variants of carbon and nitrogen ; 

 physical chemistry ; mineralogical chemistry ; pharmaceutical 

 chemistry; applied metallurgical and manufacturing chemistry ; 

 physiological chemistry including its applications to pathology 

 and biology generally; State chemistry. Caution is now more 

 than ever needed in warning the science worker to avoid the 

 danger he runs of falling into ruts on the highroad of Science, 

 since the narrowing influence of specialism may, and probably 

 does, cramp the vision, interfering with that coherent thought 

 that sees the continuity and correlation of the Universe. 



Pure Chemistry — the science dealing essentially with the con- 

 stitution, properties and transformations of what we provisionally 

 call 'matter' — co-existent throughout all time and space, presents 

 us in imagination with a picture of our world in times so remote, 

 that the interval between them and any historic period is greater 

 than one can imagine or realise. The Hon. James Norton, ll.d., 

 President of the Linnean Society, has lately given us an estimate 

 of the age of Australia which he puts at ninety-three millions of 

 years. Taking the period during which life has appeared on the 

 earth as seven hundred and four millions of years, then probably 

 one thousand millions of years will carry us back to the gaseous 

 epoch — times when seas of liquid lava afforded footing neither for 

 man, nor for any other living creature. Our terrestial history 

 may thus be summarised : — 



I. Cosmic epochs of molecular dissociation, when definite 

 compounds as now revealed to our sense-organs, did 

 not exist ; epochs, for example, when silicon and 

 oxygen could not assume the crystalline solid form 

 we so familiarly know as quartz, forming as it does, 

 a solid crust for a habitable earth. 

 II. Viscous epochs, or plastic times, when the globe began 

 to consolidate and form its crust. 



III. The long avenues of Geological Time. 



IV. The succession of Palaeolithic and Neolithic Ages. 



