Among the treasures kept for special occasions there may be pipes for soap-bubbles, a prism of some kind with which to make rainbows, a tiny mirror to make "light-birds" on the wall and ceiling, and a magnet with the time-honoured ducks and fish, if these are still to be bought, along with other articles, delicately made or coloured, which require care.

A slight thaw the day before had left every bough and twig and pine-needle covered with a moisture that had frozen in the night into glittering crystal sheaths, which flashed like millions of prisms in the sun.

The rays are collected by a lens, L{4}, tilted at an angle as shown, to form a white image of the near surface of the second prism on F. Passing a card with a narrow slit, S{2}, cut in it in front of the spectrum, any color which I may require can be isolated.

The divergence may be varied and adjusted by inclining the prism to the line of sight.

Erase the comma, and the words will describe the prism as a peculiar kind of solid; because whose will then be taken in the restrictive sense.

I bought from a peasant one of the well-known three-sided prisms with archaic intaglios of animals on the faces, and had the curiosity to inquire the virtues of it, for I was told that it was greatly valued and had been worn by his wife, who reluctantly gave it up.

"What are you so almighty prunes and prisms for, all of a sudden?

Now, by placing a rod as before in front of the patch, I have two colored stripes in a white field, and though the background remains of the same intensity of white, the intensities of the two stripes can be altered by moving the right angled prism through the spectrum.