Bill shook his head and said, “It is that old trick of Edison’s and it’s dead easy. I guess a good many of our fellows know about it. You simply punch a hole in the bulb, fill it with water, pour it back and measure the water.”
“Yes; that’s right. It is really the only sure way,” said the man, his manner showing disappointment.
“Oh, no; it isn’t, begging your pardon. Oh, no, not the only way,” said Bill.
“Well, now, how else——”
“Put water in a graduated glass, stick the bulb in up to the plaster seal and note the increase. Then break the glass and the carbon and put that in separately, deducting the last amount from the first.”
Davidson scratched his head. “Yes; that would do it, of course, too, but——”
“But you said the other was the only way,” insisted Bill.
“Oh, well, the only quick and sure way. Of course, there are other methods.”
“I’m sorry to have to disagree with you, but my method is just as sure and quicker.”
“It might do—it might do! You seem to be ready with short cuts in mechanics. How would you quickly divide a board seventeen and three-eighths inches wide into five equal parts? Can anyone here do it?”