I mention this proneness to believe that scientific men are apt to be mistaken, for it is a blame laid at their doors often by the promoters of scientific bubbles, and for a very easily understood reason, and the editors of newspapers and literary magazines can ease their consciences after publishing sensational scientific articles by reflecting on the fallibility of the followers of science. Lawyers and judges, too, make their mistakes; nevertheless, we continue to resort to them for advice; and few editors, I imagine, would dare to publish a legal opinion without consulting an authority in law. Yet we read every day so-called scientific articles in newspapers and magazines which have evidently never been submitted to competent critics. Have we not read statements of the possibility of exploding powder magazines on board ships by electric waves; of the manufacture of liquid air without the expenditure of energy; of electricity direct from coal; papers on the nebular theory, more nebulous than any nebula yet discovered? When we read a broad sheet in the morning paper setting forth a glowing scheme to manufacture power out of nothing, to what oracle can we repair to ascertain the truth? It is true that common sense might lead the reader to reflect that when he is told that the shares can now be obtained for five dollars, but in a short time they will be advanced to ten dollars, and now is the time to invest, that such good things are quickly taken up without the necessity of advertising. When the morning mail brings a prospectus of a company formed to make diamonds by electricity, a company with ten million dollars capital (why not one hundred millions?), to whom should one go to allay the fever of sudden gain? While men and women will carefully consider which line of steamships to Europe is the best equipped with engines, the efficiency of which depends upon the laws that prove the impossibility of perpetual motion, they enter at the same time upon schemes to obtain power without the consumption of work.