“I shall only,” replied she, “drop a shilling, and a piece of paper, from my bed-room window upon the lawn, and request that you will observe which of them reaches the ground first; if I am not much mistaken, you will find that the coin will strike the earth before the paper has performed half its journey.” Tom appeared perplexed, and cast an enquiring look at his father. “Come,” said Mr. Seymour, “I will perform this experiment myself, and endeavour to satisfy the doubts of our young sceptic; but I must first take the opportunity to observe, that I am never better pleased than when you attempt to raise difficulties in my way, and I hope you will always express them without reserve.” “Here, then, is a penny piece; and here,” said Tom, “is a piece of paper.” “Which,” continued Mr. Seymour, “we will cut into a corresponding shape and size.” This having been accomplished, he held the coin in one hand, and the paper disc in the other, and dropped them at the same instant. “There! there!” cried Louisa, with an air of triumph; “the coin reached the ground long before the paper.” “I allow,” said Mr. Seymour, “that there was a distinct interval in favour of the penny piece;” and he proceeded to explain the cause of it. He stated that the result was not contrary to the law of gravitation, since it arose from the interference of a foreign body, the air, to the resistance of which it was to be attributed; and he desired them to consider the particles of a falling body as being under the influence of two opposing forces,--gravity, and the air’s resistance. Louisa argued, that the air could only act on the surface of a body, and as this was equal in both cases (the size of the paper being exactly the same as that of the penny piece), she could not see why the resistance of the air should not also be equal in both cases. “I admit,” said Mr. Seymour, “that the air can only act upon the surface of a falling body, and this is the very reason of the paper meeting with more resistance than the coin; for the latter, from its greater density, must contain many more particles than the paper, and upon which the air cannot possibly exert any action; whereas almost every particle of the paper may be said to be exposed to its resistance, the fall of the latter must therefore be more retarded than that of the former body.” At this explanation Louisa’s doubts began to clear off, and they were ultimately dispelled on Mr. Seymour performing a modification of the above experiment in the following manner. He placed the disc of paper in close contact with the upper part of the coin, and, in this position, dropped them from his hand. They both reached the ground at the same instant. “Are you now satisfied, my dear Louisa?” asked her father. “You perceive that, by placing the paper in contact with the coin, I skreened it from the action of the air, and the result is surely conclusive.”