« FöregåendeFortsätt »
and they saw that a rock, seventy feet in height, forms the east wall; and that the water from the race passes to the wheels in the mill buildings, and is discharged into the river below the dam. The person who has the general care of the property, told Mr. Hilton that the mill buildings, which are of stone, are two hundred and thirty-eight feet long, and fifty-six wide; and he led the party to the pump chambers, and wheel rooms, and showed them the great wheels which are turned by the water from the race falling on them, and which work the pumps that raise water into the reservoirs.
Frank. Why need the rounds of the wheels be so much larger, than the part they turn on?
Mr. Hilton. What you mean by the part they turn on, is called the axis, and as much larger as the wheel is than that, so much power is gained.
Robert. I do not understand you, father.
Mr. Hilton. I have told you which is the axis, that must always be large enough to support the weight of the wheel: and then a
wheel, which is eight times as large round as the axis, will have twice as much power as one, that is but four times as large as the axis and so raise twice as much weight. Do you understand that?
Robert. I think I do.
Mr. Hilton. You say, you intend to be a mechanic; so you must think about such things, and try to understand them.
Harry. How strong the mill buildings look.
Mr. Hilton. Yes; they are like the wise man's house, “ founded upon a rock."
Robert. I know what you mean, father; then, “ if the floods rise and the winds blow, and beat upon them, they will not fall."
Mr. Hilton. And do you know, Robert, how we can be like the wise man?
Robert. If we do as he did.
George. But suppose we have no money to build a house?
Robert. Do you think, I know no better than that? Frank. Well, tell us what
do know. Robert. I learned the chapter, in which it is, for last Sunday; and so I can tell, that every one who knows what Jesus Christ commanded, and does it, is like the wise man.
Mr. Hilton. You are right, Robert; and when floods of trouble rise, and winds of difficulty blow upon them, they will find that the foundation on which they trust, will
support them. Come, now, we will go to the reservoirs. 66 I should like to know, (said Frank,) how much water is pumped up in one day.”
Mr. Hilton. I have heard, more than four millions of gallons every twenty-four hours.
They went up the steps that lead to the mount, on which are the reservoirs; and Mr. Hilton told them, that the water in them, was one hundred and two feet above low tide; and fifty six above the highest ground in the city. In a few moments, George saw Mr. Elmer and a stranger, walking towards the place where he was standing, and as Mr. Elmer came near, he looked pleased, and said, “this is a better place for you to be, than on the election ground." What does your cousin thing of it, George?
George looked at Frank for an answer, who said, “It is worth coming to see, and these are great works, to be sure; but I see no need of bringing the water up here, with so many wheels, and pumps, and pipes.
Mr. Elmer. How do you think it could be managed better?
Frank. A reservoir might have been made by the side of the river, below the dam, and the water taken through a race into it; and then the water, out of the reservoir, might run through the pipes, that are laid to lead it into the town.
Mr. Elmer. Your plan might do, my lad, if the water was only wanted to run through the pipes, and not to be raised again from them.
Frank. It could be raised by the hydrants, as it is now.
Mr. Elmer. You know less about the nature of water, perhaps, than you think you do.
Frank. I ought to know about it, for I live near a river, and swim in it pretty often.
Robert. I wish I could swim.
Mr. Elmer. When you are older, you must learn; for it may be the means of saving your life, or of saving others, who are in danger of drowning. Begin to learn to swim in water, that is at least, not so deep by a foot, as you are tall; and remember what I tell you, water is always a fourth part deeper than it ap
pears to be.
Harry. Do you mean, sir, that if water looks as if it was three feet deep, we may be sure, it is four feet. Mr. Elmer. Yes. If, at any time, you
find yourself sinking in deep water, a very slight motion will bring you up again; and then, if you can turn on your back, and keep only your face above the water, you may do well; but if you struggle, and try to throw yourself high above the water, you will sink again; and many such struggles will spend your strength.
Frank. Will you tell me, sir, why it would not do, to carry the water into the pipes, in the way I said, instead of bringing it first up into these reservoirs.
Mr. Elmer. In many parts of the city, where the water is to be used from hydrants, the ground is higher than the river Schuylkill is: and water is wanted, too, to use through pipes, sometimes into the upper stories of high