466 
LIVERPOOL CHEMISTS’ ASSOCIATION. 
the screen, with remarkable definiteness, Maule and Polyblank's photographs of Lord 
Posse, Lord„ Brougham, Professors Faraday, Graham, Brande, Miller, Taylor, Redwood.. 
Bentley, Owen, Carpenter, etc.; also of some eminent pharmaceutists, among which we 
noticed those of Messrs. Morson, Deane, and the late Jacob Bell. Dr. Edwards gave a 
succinct biographical sketch of many of these gentlemen, noticing their chief scientific 
labours as their portraits appeared on the screen. Finally, some photographs of the 
moon in its different phases, and the movements of a chronometer watch in action, were 
beautifully depicted on the screen; and the audience frequently, during the preceding 
illustrations, manifested their gratification by hearty applause. An interval for pro¬ 
menade and refreshments was announced, hut the zest for creature comforts, which were 
supplied throughout the evening on a liberal scale, proved to be very subjective with a 
great many to the desire for intellectual observations and study, for in this interval large 
numbers beset the microscopic exhibitors on the geological gallery, to obtain a sight of 
the various objects shown under their very powerful binocular instruments. 
The objects which appeared to attract most favour here were the diatoms, polycystins, 
and the ova of the salmon in various stages of development. Dr. Edwards, during this 
interval, exhibited some brilliant experiments with Geissler’s vacuum tubes, and several 
fluorescent liquids and glasses ; he likewise showed the effect of vibration by the produc¬ 
tion of figures on a horizontal plate covered with sand, and also by delineating the 
figures of a common chord, illustrating the laws of sound as investigated by M. Lissajou 
and others. 
At half-past eight the gong once more summoned the company to the theatre. The 
President introduced Wm. Crookes, Esq., F.R.S., of London, and expressed his confi¬ 
dence that the high anticipation which he, i^fcommon with the audience, had entertained 
of the pleasure of hearing Mr. Crookes, would be fully gratified, and concluded by saying, 
that Mr. Crookes well merited the dignity of being ranked with original discoverers, by 
his successful labours in an unexplored plain, and by which he had the honour of en¬ 
riching chemistry with the discovery and development of a new elementary body- 
thallium. He had great pleasure in calling upon Mr. Crookes to favour them with his 
lecture “ On the Recent Application of intense Chemical Action to the Production of 
Heat and Light.” Mr. Crookes, who on coming forward was warmly applauded, pro¬ 
ceeded with the subject of his lecture, premising that whenever chemical action took 
place, it was always governed by one particular kind of force—chemical affinity; and 
although in the manifestation of this force with certain classes of bodies, varied and sur¬ 
prising effects presented themselves, still such effects could only be regarded as degrees 
of the intensity of chemical affinity. In the oxidation of iron in moist air, the decay of 
woody fibre, the change of saccharine fluids in contact with a fermenting agent, and of 
the effete matter of the blood in the lungs of living animals, as true a combustion of 
certain matters took place as was evidenced in the burning of a coal fire or of the gas in 
the lamp before him. In those, however, the action was slow and diffused, while in 
these it was rapid and compressed ; hence the apparent difference in the results. Still, 
by judiciously conserving the effect where the action appeared so feeble as to be almost 
inappreciable to casual observation, as in the galvanic battery, great intensity could, be 
acquired and manifested. He then gave illustrations of powerful and rapid chemical 
action by means of sulphuric acid and water, the burning of potassium in water, the 
ignition of chlorate of potassa and sugar by sulphuric acid, the burning of gun cotton, 
magnesium, etc., and compared such bodies to so many springs, ready to exert their 
tensile force in the powerful manner exhibited. He then proceeded to demonstrate that 
many bodies which were usually regarded as manifesting but a weak tendency to undergo 
chemical action, could be made, by altering slightly their condition, to exhibit it in a 
powerful degree. In illustration, some finely-divided metallic iron was burned in the 
flame of a spirit lamp, and by comparison the lecturer proved that this metal was much 
more combustible than carbon or gunpowder. He next proceeded to enlarge upon the 
consequences which attend the application of these phenomena to various purposes, 
dwelling particularly upon the nature of the light which was afforded, and the data 
which it presented for determining chemically the constitution of complex substances. 
He concluded his interesting lecture by exhibiting the magnesian and electric lights side 
by side, thus showing the remarkably superior intensity of the latter. Mr. Crookes, at 
the conclusion of his lecture, was warmly applauded. 
Not the least interesting feature of the evening was the exhibition of the Chromeido- 
