such discoveries as two centuries ago would have sent the discoverer’s to the flames.  The liquefaction of oxygen; the existence of radium, of helium, of polonium, of argon; the different powers of Roentgen and Cathode and Bequerel rays.  And as we may finally prove that there are different kinds and qualities of light, so we may find that combustion may have its own powers of differentiation; that there are qualities in some flames non-existent in others.  It may be that some of the essential conditions of substance are continuous, even in the destruction of their bases.  Last night I was thinking of this, and reasoning that as there are certain qualities in some oils which are not in others, so there may be certain similar or corresponding qualities or powers in the combinations of each.  I suppose we have all noticed some time or other that the light of colza oil is not quite the same as that of paraffin, or that the flames of coal gas and whale oil are different.  They find it so in the light-houses!  All at once it occurred to me that there might be some special virtue in the oil which had been found in the jars when Queen Tera’s tomb was opened.  These had not been used to preserve the intestines as usual, so they must have been placed there for some other purpose.  I remembered that in Van Huyn’s narrative he had commented on the way the jars were sealed.  This was lightly, though effectually; they could be opened without force.  The jars were themselves preserved in a sarcophagus which, though of immense strength and hermetically sealed, could be opened easily.  Accordingly, I went at once to examine the jars.  A little—­a very little of the oil still remained, but it had grown thick in the two and a half centuries in which the jars had been open.  Still, it was not rancid; and on examining it I found it was cedar oil, and that it still exhaled something of its original aroma.  This gave me the idea that it was to be used to fill the lamps.  Whoever had placed the oil in the jars, and the jars in the sarcophagus, knew that there might be shrinkage in process of time, even in vases of alabaster, and fully allowed for it; for each of the jars would have filled the lamps half a dozen times.  With part of the oil remaining I made some experiments, therefore, which may give useful results.  You know, Doctor, that cedar oil, which was much used in the preparation and ceremonials of the Egyptian dead, has a certain refractive power which we do not find in other oils.  For instance, we use it on the lenses of our microscopes to give additional clearness of vision.  Last night I put some in one of the lamps, and placed it near a translucent part of the Magic Coffer.  The effect was very great; the glow of light within was fuller and more intense than I could have imagined, where an electric light similarly placed had little, if any, effect.  I should have tried others of the seven lamps, but that my supply of oil ran out.  This, however, is on the road to rectification.  I have sent for more cedar oil, and expect to have before long an ample supply.  Whatever may happen from other causes, our experiment shall not, at all events, fail from this.  We shall see!  We shall see!”