“And how do they manage it?” asked Louisa.
“As soon as the whale dives,[(35)] after having been wounded, it draws out the line or cord of the harpoon, which is coiled up in the boat, with very considerable velocity. In order, therefore, to prevent any accident from the violence of this motion, one man is stationed with an axe to cut it asunder, if it should become entangled; while another, with a mop, is constantly cooling with water the channel through which it passes.”
“The kite is now at a considerable height,” observed Tom; “but look at the string, how bent it is! I have repeatedly endeavoured to pull it straight, but without success.”
“How could you have expected to succeed in the attempt? Consider the weight of such a long line of string.”
“Then it is not the pressure of the atmosphere which gives it that curved form?”
“Assuredly not: have you so soon forgotten that the air presses equally in all directions, and would therefore tend to straighten, as much as to give a curved direction to the string? But, as you now appear to have let out the whole of your string, suppose you allow the kite to enjoy its airing, while we proceed to consider the philosophy of its ascent, and the nature and direction of those forces by which it is effected.”
“The kite pulls so amazingly hard,” cried Tom, “that unless I fix the string securely around the tree, we shall run the chance of losing it.”
“I am well aware of the force it exerts,” replied his father. “Dr. Franklin has said, that, with a good kite, a man unable to swim might be sustained in the water, so as to pass from Dover to Calais; but I agree with him in thinking, that a packet would be a much safer, as well as a pleasanter mode of conveyance.”
“Now, then, for your explanation of the kite’s ascent. Unless I am mistaken, you will find the subject much more complicated than you imagine,” said the vicar.
“Not at all; Tom, who, I trust, has a perfect acquaintance with the composition and resolution of forces, will very readily understand the explanation I propose to offer. I admit, however, that there are some few points in the enquiry, which cannot be successfully treated without a knowledge of the higher branches of the mathematics; but I shall, of course, avoid all such difficulties.[[42]] Can you tell me, Tom, what advantage is gained by your running with the kite?” asked Mr. Seymour.