When Sir Isaac Newton changed his residence and went to live in Leicester Place, his next door neighbour was a widow lady, who was much puzzled by the little she observed of the habits of the philosopher. One of the Fellows of the Royal Society, called upon her one day, when among other domestic news, she mentioned that some one had come to reside in the adjoining house, who she felt certain was a poor mad gentleman. “And why so?” asked her friend. “Because,” said she, “he diverts himself in the oddest way imaginable. Every morning when the sun shines so brightly that we are obliged to draw down the window-blinds, he takes his seat on a little stool before a tub of soap-suds, and occupies himself for hours blowing soap-bubbles through a common clay-pipe, which he intently watches floating about until they burst. He is doubtless,” she added, “now at his favourite diversion, for it is a fine day; do come and look at him.” The gentleman smiled; and they went upstairs, when after looking through the staircase window into the adjoining court-yard, he turned round and said, “My dear lady, the person whom you suppose to be a poor lunatic, is no other than the great Sir Isaac Newton studying the refraction of light upon thin plates, a phenomenon which is beautifully exhibited upon the surface of a common soap-bubble.” The principle, illustrated by the examples we have given, has been efficiently followed by the Directors of the Royal Polytechnic Institution in Regent Street, London. Even the simplest models and objects they exhibit in their extensive halls and galleries, expound—like Sir Isaac Newton’s soap-bubble—some important principle of Science or Art. On entering the Hall of Manufactures (as we did the other day) it was impossible not to be impressed with the conviction that we are in an utilitarian age in which the science of Mechanics advances with marvellous rapidity. Here we observed steam-engines, hand-looms, and machines in active operation, surrounding us with that peculiar din which makes the air “Murmur, as with the sound of summer-flies.”