Thrilled and animated by this success, I hastened to apply the same plan of magnifying segment by segment to my photograph of Jupiter. But, alas, although something suggestive did appear, or so I fancied, the image grew dimmer with each analysis, until, under the higher powers, it disappeared, and the grainings of the card superseded the planet. Had I not proved that my principle was good in the case of the Swiss sign-board, I should now have given it up as the whim of an over-excited brain. But now I thought only of the assertion of the daguerrotypist, that "the nitrate was limited in sensitiveness only by the imperfection of the materials," (i. e. plates, glass, reflectors, etc.,) and I had heard the same repeated by the paper which had finally replaced the picture it held. I now determined to risk on the experiment the elegant steel plate on whose polish I had spent so much pains and time. I took the portrait of Jupiter thereon, and fixed it forever. This time I could not be mistaken in supposing that as the field of vision shrank some strange forms appeared; but I could be certain of none which were essentially different from those revealed by the largest telescopes. My narrowing and intensifying process then began to warn me of another failure: when I had reached the last point at which the image could be held at all, the grain of the steel plate was like great ropes, and it was only after resting my eyes for some time, then suddenly turning them upon it, that I could see any picture at all. For an instant it would look like an exceedingly delicate lichen,--then nothing was visible but huge bars of steel. Ah, with what despair did I see the grand secret which had so long hovered before me and led my whole life now threatening to elude and abandon me forever! "But," I cried, "it shall not go so easily, by Heaven! If there be a genius in the casket, unsealed it shall be!" I resolved to give up steel for some metal or substance of finer grain. I almost impoverished myself in purchasing plates of the finer metals, before it occurred to me to try glass, and had to laugh at my own stupidity when I discovered that in the last analysis glass showed much smoother than any of the rest. I immediately obtained a great many specimens of glass, and spent much time in subjecting them to my lenses only to see how much fibrous appearance, or unevenness, could be brought before the eye from a smooth surface. I found one excellent specimen, and gave myself up to grinding it to the utmost extent consistent with its strength.