After a good deal of trouble with the collodion, Jim finally prepared a smooth plate, which he allowed to wait thirty seconds, and then carefully lowered it into the silver bath. After a few seconds he raised it, and found it covered with streaks. [Illustration: OLD SPRIGGINS'S GRAPE ARBOR.] "Put it back," said Fred; and in it went. In about thirty-five seconds more, it was of that fine opal tint mentioned by the Professor. It was then placed in the slide and carried to the camera. Jim pulled out his watch, and with a forced smile to hide his nervousness said, "Go," and Fred drew up the sliding door. When the plate had been exposed long enough, as he thought, Jim cried, "Time," the door was closed, the slide taken from the camera, and the boys returned with it to the dark chamber. The plate was then taken from the slide, and Fred, seizing a bottle, poured its contents over the opaline surface. "As if by magic--" Jim began. "Nothing appears," continued Fred, as he saw in astonishment every trace of silver disappear from the plate, and the bare tin surface left exposed. "I can't see through that," he added, in dismay. "I can," answered Jim: "you were in such a hurry that you poured on the fixing solution instead of the developer, and of course that has dissolved everything." Jim then prepared another plate with great care, placed it in the camera, exposed it for such time as he thought fit, and returned with it to the dark chamber. Removing it from the slide, he carefully poured on the developer. By degrees the cloud on the surface dissolved, and a picture slowly appeared, very imperfect, but still a picture. [Illustration: GLASS BATH AND DIPPER.] "Isn't that splendid?" said Fred, enthusiastically; "it's just as natural as life." Jim, cool and quiet as usual, washed the plate well with water, and cautiously poured on the fixing solution, when the yellow coating of the picture vanished, and old Spriggins's grape arbor came out in clear, sharp lines. "Now, Fred," said he, "you calm down a little, and varnish this." "All right," answered Fred; and having lighted the spirit-lamp, he poured on the varnish, and held the plate over the flame; but, alas! there was a fizz, a vile smell, a great deal of smoke, and the pretty picture was a mass of paste. "I won't have anything more to do with this part of the work," said Fred, impatiently, throwing the spoiled plate on the floor. "I can play doctor's shop, and mix up solutions as well as anybody, but this endless dipping, washing, and drying takes more patience than I possess. I shall leave that to you, Jim." "One more trial, and a perfect picture," answered Jim, quietly.