The little tent was lined with tar paper which had no glaze and was of an intense black, expelling all white rays which might be injurious to his exposed plates, the red rays not doing this.

When his plates were dry Billy put one of them in his frame, which contained a sheet of plain glass, and slipped one of his sensitized sheets under it, closing the frame with a cleat under the back.

Passing this in front of the lamp for a few moments, he removed the paper and placed it in a tray containing a developing fluid, when at once the print began to show very plain.

When it was dark enough he removed it from the tray and put it in another which contained a fixing fluid which prevented further development, and presently washed it thoroughly in clear water.

“What do you think of that?” he asked Jack, with a tone of triumph.  “It is convincing, isn’t it?”

“It shows Herring talking to Jenkins, but you cannot tell what he says,” remarked Jack with a smile.

“No, I have not got to taking talking pictures yet,” laughed Billy, “but the very fact that he was with Jenkins at all means something.”

CHAPTER XXII

EVERYTHING IS SETTLED

The boys left the little developing room after putting out the lights and seeing that all was safe and that there was no chance of fire, and made their way to the middle of the camp, where there was an open space in which a number of the boys had gathered to amuse themselves.

There were several good singers among the boys and a number of them had musical instruments, banjos, guitars and mandolins, so that it was an easy matter to get up a concert at any time, the boys whiling away many an hour in this fashion.

Some of the musicians had already begun to play when the three boys arrived, their absence not having been noticed, and now Arthur, who played the banjo, called upon a number of the boys to join in a plantation melody and later a number of the old and new college songs.

Blaisdell had a good voice and he started the songs, the others quickly joining him, till there were a dozen or more and fifty for the chorus, the woods fairly ringing with the melody, which could be heard a mile away by the men who had tried to stop the boys from surveying.

“Huh! they’re singin’ up there!” growled the big man.  “We hain’t got nothin’ yet, an’ that young feller said he was goin’ to pay us.”

“We orter got pay afore we done anythin’, that’s the trouble,” growled Jenkins.  “He was a sneak.  Arter promisin’ to pay us for makin’ trouble, he run away an’ left us.”  “Mebby if we tell the ingineers who he is they’ll pay us,” suggested one of the men.  “We gotter get something out o’ this.”

“That’s true enough,” echoed Calthorpe.  “We can’t do things for nothing.  We gotter make something.”

“I guess if we tell the young feller that we know who it was what sot us ag’in’ him he’ll pay us something,” added Jenkins.  “It don’t make no difference to me where I get money, so long as I get it.”