TESTS
"I suppose now we'll all get blown up, or poisoned, or something," Bill
said to Tony, after telling of the eclipse of Luigi Malatesta.
"Oh, no; the Malatesta are foemen worthy of our steel, to agree by an
English poet; is it not?"
"'Foeman worthy of a steal,' I guess you mean," laughed Gus.
"Yes, that's more like it. I wouldn't trust that pig-faced villain
across a ten-acre lot with a ten-cent piece!" declared Bill.
"The soul of honor doesn't dwell in a husky guy who'd strike a cripple,"
said Gus. "And I bet a cow he's going to stir up more trouble around
here before he quits maneuvering."
Tony made no reply, but stood for a long time, gazing at the floor.
Presently only the sound of tools and machines was heard in the shop.
It is not probable that Luigi told of the precise outcome of his clash
with Bill and Gus, though he may have said enough to influence sophomore
sentiment against Bill's standing in the school. At any rate, the
feeling grew in strength and spread until it became a subject of comment
among freshmen and seniors who were inclined to sympathize with the
brainy and keen-witted lame boy. At least he had many friends, both high
and low, and most of the teachers admired him openly.
So far the sentiment had been rather more doubtful and erratic than
determined. There had been nothing to warrant the assumption that Bill
thought himself more intelligent than the sophomores, or members of his
own class. His radio knowledge was somewhat a thing apart and in that he
shared with the less obtrusive Gus.
And then the lightning struck, suddenly and hard. Once each week an
outsider from the engineering department of some big industrial plant,
or large university, lectured to the entire student body of the
Marshallton Tech in the assembly-room, and there were some of these
talkers who got much pleasure out of it. Not only was it interesting to
hold forth to a lot of eager, responsive boys on subjects that elicited
their curiosity, as the building of great dams and bridges, the
tunneling under mountains, the erection of mighty machines, but it was
also diverting to hear their various comments which also led to a
comparative estimate of their understanding.
Davidson, chief mechanical engineer of a great mill building
corporation, was especially interested in the personal equation
concerning the students, particularly after Bill Brown bad asked him a
lot of questions, some of which he had replied to rather lamely. Even
more as a matter of getting back at this young investigator who sat with
a crutch held before him and regarded these replies with a smile than
for the desire to measure minds, Davidson gathered a few catch problems
that were stumpers, and upon his third visit, after talking awhile he
switched off on the subject of problems, short cuts to solutions and
then put a question, looking hard at Bill, as though uttering a
challenge.
"Now, how would you go about it," he shot at his audience, "if you were
asked to measure the cubic contents of an electric light bulb?"
A number of smiles greeted the question; these may have been from lads
mostly in the advanced courses who knew the trick. The lecturer asked
for hands to be raised by those who thought they could do it, and noting
with satisfaction that the crippled boy was not among the number who
responded, he began hearing them, one at a time.
"Measure it outside and allow for the thickness of the glass," said one
fellow.
"But how about the carbon inside?" asked Davidson.
"Break the glass and measure the loop," called out a soph.
"How many of you would go at it in that way?"
A number of hands went up, some rather reluctantly, as though their
owners scented a trick.
Davidson still eyed the cripple. "How would you do it?" he asked.
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?"
"That's easy," said Bill.
"Well, then, how about this one? If a pint cup----"
"Your question about dividing the board is too interesting to pass over
so hastily," interrupted Professor Search. "If you will pardon me, I
would suggest that Brown go to the board and demonstrate it."
"Will you let Grier do it? He knows that old trick, and he is handier
with the chalk than I."
Gus went forward, took a two-foot rule from his pocket and laying off
two parallel lines seventeen and three-eighths inches apart, laid the
rule diagonally across them so that the space would measure twenty
inches. Then he ticked off at the figures four, eight, twelve and
sixteen. Laying the rule straight across from an outer line to the first
tick he turned and announced:
"Each space is practically three and fifteen-thirty-seconds inches."
This brought forth something like applause, along with many very audible
remarks, such as: "Pretty cute." "Handy." "Where'd he get it?" "Can't
fool either of 'em, can you?" "Those fellows are practical, that's
sure."
Mr. Davidson smiled sort of absently. He had to give approval, but
dropped the question rather abruptly, going back to his last problem.
"Now, see if you can tell me this: I have a half-pint cup even full of
water, the liquid exactly level with the edge of the glass. About how
many one-inch brads must I drop into the cup before the water overflows?
Water, you understand--not oil, nor molasses. This is an old experiment
and it concerns a well-known physical law. If anyone has seen it done he
will kindly remain silent. Now, who will make a guess as to the number
of nails?"
Every brow was wrinkled, except those of a few conclusion jumpers of
whom there must be some in every crowd. One of these latter fellows
shouted at once: "About a half dozen and it'll slop over!"
"It'll take only one or two," said another.
"Not more than a dozen, anyway."
But the others, mostly lads capable of real mental exercise, were all
cudgeling their brains. It was a subject which had much to be taken into
consideration. Presently one senior spoke up:
"It ought to take more than an ounce of them."
"Nearly as much, anyway."
"More. That'll fool you mightily."
"It looks as though a few brads would do it, but it will take a lot."
"And why?" asked Mr. Davidson. "Come, what do you say about this?" He
again appealed to Bill, turning then also to Gus.
"Well, sir, I think I can see that it will take nearly all of that box
of brads, perhaps a hundred. It is a matter of cohesion and even water
possesses that, so that to overflow, it will have to rise a good deal
above the rim. The area of the glass plus the rise that will be required
for the overflow will be, in solid contents, easily as much as that box
of loosely filled brads; if they were melted down they wouldn't be
greater than the water area. It is a good deal like the loading of a
boat: the displacement is a uniform, compact mass; the load is a jumble
with more air space than material. And it is like the floating of a
heavy iron pot."
For answer the lecturer turned and drew a half-pint of water in a glass,
brought from his pocket a box of brads and began dropping, one at a time
and counting, them into the water. There was profound silence. As the
number increased, reaching above two score of the small nails, there
began to be heard comments here and there.
"Zowie! Who'd a thunk it?"
"Better just dump 'em all in and start over."
"Don't reckon those nails are soaking the water up; eh?"
"If it were molasses you could fill it half full of brads before it
would slop over."
"Say, look, he's up to sixty! Would you believe that?"
"Hey there, Fatty, you guessed one nail; didn't you----"
"Sixty-eight, sixty-nine, seventy; looks to me like a spill pretty
soon."
"When the freshet starts----"
"It'll drown a lot of people."
Mr. Davidson stopped dropping the nails into the tumbler and held up his
hand.
"There it goes, boys--the first drop over! Eighty-two brads. You can see
who guessed best. The cohesion of the liquid explains it, as our young
friend here has said. I'm glad you have one thinker among you. Now I
want to tell you something about the installation of machinery by
individual motors driven by a central generator, as compared to the
drive from a mill long countershaft and pulleys." And he proceeded with
his talk.
Yes, the lightning had struck. From this moment the respect shown to
Bill, and to Gus also, by those who had no desire to do otherwise was
really almost overdone, his classmates being generally proud of him, and
the teachers and seniors pleased to have him a member of the school. But
the sophs mostly grew more inclined to consider both boys a menace to
their peace of mind.