NELSON ASSOCIATION.

Colonist, Volume XII, Issue 1215, 31 August 1869, Page 3

NELSON ASSOCIATION.

On Wednesday evening, August 4th, the Nelson Association held their first monthly meeting, the Treasurer, C. Hunter Brown, Esq., occupying the chair. A letter was read from Sir David Monro accepting the office of President of the Association, &nd several new members were proposed. Dr. Irvine then read a short paper " On the divisibility of matter, as illustrated by the phenomena of luminous combustion." Having prepared the way for his argument by an illustration drawn from the production of waves in a body of still water, he contended that a minimum estimate of the number of atoms of a combustible body might be arrived at by comparing the loss of weight undergone by it in a given time, with the number of waves of light caused by its .combustion during the same period, on the principle that the light being caused by the chemical union of atoms, and each wave of light necessarily implying the combustion of at least one atom of the burning substance, its atoms must be at least as numerous as the luminous undulations. He then showed that optical philosophers had computed the number of waves or undulations for each kind of light; that they amounted to forty thousand in every inch of a ray of white light, and that the velocity of light being known as about two hundred thousand miles per second, the number of waves of light received by the eye and emanating from the combustion of a common candle could be readily calculated, and compared with the weight of it consumed. Having given the numerical data for the computation, the Doctor stated as the result, that each grain of tallow would contain at least 3,500 millions of atoms, each of which again contains at least three other atoms, namely, oxygen, hydrogen, and carbon. A discussion ensued, terminating in a vote of thanks to the author of the paper, after -which the society adjourned until the first Wednesday in September.