his bill at the inn, he added fifteen pieces more, to serve to entertain M. Gros and M. Bureau for some days, and in the meantime he ordered a supper, that he might, on his return, have the pleasure of supping with these two gentlemen. He went out, but never returned, leaving behind him the greatest regret and admiration. It is needless to add that M. Gros and M. Bureau continued to enjoy themselves at the inn till the fifteen pieces which the stranger had left, were exhausted." Narratives such as these led even Bergman, a very able chemist of the period, to take the ground that "although most of these relations are deceptive and many uncertain, some bear such character and testimony that, unless we reject all historical evidence, we must allow them entitled to confidence." A much more probable explanation is that the relators were either dreaming or deceived by clever legerdemain. Of the possibility or impossibility of converting the more common metals into gold or silver, it would be rash to give a positive opinion. To say that gold, silver, lead, copper, etc., are elements and cannot be changed, is merely to say that we have not been able to decompose them. Water, potash, soda, and other substances, were at one time considered elements, and resisted all the efforts of the older chemists to resolve them into their components, but with the advent of more powerful means of analysis they were shown to be compounds, and it is not impossible that the so-called elements into which they were resolved may themselves be found to be compounds. This has happened in regard to some substances which were at one time announced as elements, and it is not impossible that it may happen in regard to others. The ablest chemists of the present day recognize this fully and are prepared for radical changes in our knowledge of the nature and constitution of matter. Amongst the new views is the hypothesis of Rutherford and Soddy, which, as given by Sir William Ramsay, in a recent article contributed by him to "Harper's Magazine," is that, "atoms of elements of high atomic weight, such as radium, uranium, thorium, and the suspected elements polonium and actinium, are unstable; that they undergo spontaneous change into other forms of matter, themselves radioactive and themselves unstable; and that finally elements are produced, which, on account of their non-radioactivity, are as a rule, impossible to recognize, for their minute amount precludes the application of any ordinary test with success. The recognition of helium however, which is comparatively easy of detection, lends great support to this hypothesis."