It may be added that the well-diffused light of the new system contrasts very forcibly with the black dense shadows cast by the electric light, and forms a strong argument in favour of the former. The power required to supply air is not large, about one-eighth horse-power being found sufficient for each light. Thus, a small air-compressor of five horse-power can readily produce abundant pressure for forty lights. When employed on a large scale, and laid down permanently, other economies and conveniences can be effected, as, for example, the erection of a central tank arranged to feed all the burners. Turning now to the oil employed, it may be noted that almost any oil may be utilised, the crude and waste products of oil and gas works being found to yield excellent results. This fact alone, enabling products of small value to be rendered serviceable, should advance the light in no small degree. There is beyond all question a large field for any illuminating agent, which can be readily erected in goods-sheds, ship-yards, or engineering works, and can be worked at moderate cost. Whether or not this adaptation of hydro-carbon oil will fulfil all the conditions necessary to render it a commercial success and lead to its wide development, time alone can tell. We have, however, shown that it has already done good work, and promises well for the future. MR G. A. SALA ON LABOUR IN AUSTRALIA. Mr G. A. Sala, recently addressing the representative of an Australian journal, said: ‘I recognise that labour is needed everywhere in Australia—more working men, more domestic servants, more young men, more intelligent men, more Scotsmen—as many more as ever you like. I think I have also been able to discern the people who are not required here. These are the black-sheep of good families, loafers, idlers, young men who come out and spend their money, drift into dissolute habits, get remittances to take them home again, where they do nothing but abuse the colonies, of which they know nothing, and in which their presence was likely to do more harm than good. I have been preaching lay sermons for a good many years; and were I not too old and too wicked, I would get into some pulpit at home and preach as a minister, for certainly ministers have more influence over their congregations than lecturers have over audiences. I would say to my hearers: “My capable, hard-working, shrewd, intelligent brethren, go out to Australia. You and your wives and your children, go out, work hard; and be assured that, with or without capital, you will, by hard working, frugality, and sobriety, greatly better your condition. Not only that, but you will also better those whom you leave behind. You will give more and more backbone, more and more muscle, more and more red blood, to the body politic of Australia.” But I would also add: “My idle brethren, my stupid brethren, my wicked, needy brethren, my vicious brethren, my drunken brethren, stop at home and gravitate to your