My father had left me enough property to enable me to carry forward the investigations and experiments to which all voices seemed to call me. I had an upper room prepared with a skylight and all other appliances. I purchased an excellent instrument, and some very strong diameters for magnifying photographs. The trials I had made convinced me that the minuteness and extent of objects photographed were limited only by the comparative coarseness of the materials _through_ and _on_ which the object passed. So I was very particular in selecting lenses. Further trials, however, led me to believe that the plate was still more important. Obtaining a steel of perfect grain, I spent days in giving it the highest polish it would bear, and kept it ready for any important office. By means of a long and bright tin reflector, (the best,) my artificial light was ready, in case I should desire to photograph at night; and, indeed, it was the hope of making some astronomic discovery that was leading me on. Calm and clear was the night on which I brought these my treasures forth. Jupiter was blazing in the heavens, and challenged Art to seize his majestic lineaments. It turned out a point of fire much like that which my master had exhibited to me. I mixed a finer nitrate, repolished my plate, and was this time rewarded by seeing, under all the diameters which I had, the satellites also. Very much thrilled even with this degree of success, and taking the picture on paper, I put my plate away, and set myself to study what I should do next. It had not yet occurred to me to inquire of myself what definite thing I really was after. My deepest hope was in the undefinableness of its object: I knew only that a clear idea (and Plato says all clear ideas are true) of the subtile susceptibilities of nitrate of silver, _limited only by materials_, had engendered within me, through much pondering, an embryo idea, to the development of which my life was intuitively consecrated. I would not define it to myself, because I felt (intuitively, also) that it was something illimitable, therefore indefinable.