rrect, is it not, father?"

Mr. Ribsam took another puff or two, as if to make sure that his boy was
not leading him into a trap, and then he solemnly nodded his head.

"Dot ish so,--dot am,--yaw."

"Then if Philadelphia has one hundred people for its population, New
York has one hundred and fifty?"

"Yaw, and Pheelatelphy has feefty per cent. less--yaw, yaw, yaw!"

"Hold on, father,--not so fast. I'm teacher just now, and you mustn't
run ahead of me. If you will notice in this problem the per cent. in the
first part is based on Philadelphia's population, while in the second
part it is based on the population of New York, and since the
population of the two cities is different, the per cent. cannot be the
same."

"How dot is?" asked Mr. Ribsam, showing eager interest in the reasoning
of the boy.

"We have agreed, to begin with, that the population of Philadelphia is
one hundred and of New York one hundred and fifty. Now, how many people
will have to be subtracted from New York's population to make it the
same as Philadelphia?"

"Feefty,--vot I says."

"And fifty is what part of one hundred and fifty,--that is, what part of
the population of New York?"

"It vos one thirds."

"And one third of anything is thirty-three and one third per cent. of
it, which is the correct answer to the problem."

Mr. Ribsam held his pipe suspended in one hand while he stared with open
mouth into the smiling face of his son, as though he did not quite grasp
his reasoning.

"Vot you don't laughs at?" he said, turning sharply toward his wife, who
had resumed her knitting and was dropping many a stitch because of the
mirth, which shook her as vigorously as it stirred her husband a few
minutes before.

"I laughs ven some folks dinks dey ain't shmarter don dey vosn't all te
vile, don't it?"

And stopping her knitting she threw back her head and laughed
unrestrainedly. Her husband hastily shoved the stem of his pipe between
his lips, sunk lower down in the chair, and smoked so hard that his head
soon became almost invisible in the vapor.

By-and-by he roused himself and asked Nick to begin with the first
problem and reason out the result he obtained with each one in turn.

Nick did so, and on the last but one his parent tripped him. A few
pointed questions showed the boy that he was wrong. Then the hearty
"Yaw, yaw, yaw!" of the father rang out, and looking at the solemn
visage of his wife, he asked:

"Vy you don't laughs n