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satisfied. Of all these matters the supply, however large, is 
limited and costly, the cost increasing rapidly as the consump- 
tion becomes greater. The gradual but steady improvement 
in the quality and purity, and the great reduction in the cost, of 
gas has been met by a corresponding increase in the quantity 
used. 
When so much better and cheaper a light than candles or 
oil lamps was first introduced and found so useful, it became 
almost inevitable that the old sources of artificial light should 
also be improved. Thus candles, as we have said, are now of 
greatly improved quality ; they are made from various mate- 
rials, formerly thought altogether inapplicable ; the best of the 
present day are hardly more expensive than the worst of half 
a century ago ; while in all important respects, the very mate- 
rials that rendered the tallow candles of former times a 
nuisance to everybody, being now separated and applied to 
their proper uses, are found to possess a value positively 
greater than that of the combustible material itself, which 
they at one time interfered with and injured. 
The scientific principles of consuming fuel so as to obtain 
light being also now better understood, there is far less waste 
than before in our lamps, and some of them are models of 
mechanical art, obtaining the most perfect result at the 
smallest expenditure of material. In all these matters the 
mechanical improvements and the application of chemical 
principles have gone hand in hand. 
It is altogether impossible to exaggerate the value and 
importance of light; and it is certain that everything done 
to facilitate the means of obtaining and distributing artificial 
light cannot fail to be of general benefit to mankind. And if, 
looking at the glorious orb of day, and remembering all its 
life-giving properties, we exclaim with the poet — 
“ Hail ! holy light — offspring of Heaven first horn,” 
we may, with equal propriety, regard in artificial light, however 
obtained, a younger, but hardly less useful and important crea- 
tion, always at hand, requiring a certain development of human 
intelligence to render it available, but rewarding’ us by com- 
municating a means of moral and intellectual light, as well as 
that physical illumination that is so useful and so indispensable. 
