BOYS' OWN COLUMN.

Auckland Star, Volume LXII, Issue 252, 24 October 1931, Page 2 (Supplement)

BOYS' OWN COLUMN.

THE DISCOVERY OF THE MICROSCOPE,

SCIENCE'S GREAT ADVANCEMENT.

Dear Boy*,—

The other day while I was enjoying a week-end with a friend, his voting son asked me if I would like to look through a microscope. I was agreeably surprised to discover the extent to which this tiny immature glass was able to magnify. The tiny piece of coloured silk which we Were observing ehowed up like coarse coal sacking.

Nobody can say when man discovered the magnifying power of a. lens. As soon a* glass was known, the idea to magnify vision would probably be noticed by many an observant eye, for most people quickly notice that a bottle full of water enlarges letters and objects seen through it.

Although lenses were used as spectacles in the thirteenth century to assist the failing sight of old people, four more centuries passed by before the microscope was more than a crude toy. Eventually Kobert Hooke made lenses of considerable magnifying power out of globules formed by using threads of spun glass. : But to the famous Dutchman, Anthony van Leeuwenhoek, fell the credit of being the first man to see bacteria. He found them first in the tartar of the teeth. To my surprise, he said, "I found it contained many very small animaculae, the motions of which were very pleasing to behold. The motions of these little creatures, one among another, may be likened to that of a great number of gnats or flies disporting in the air."

He was also probably the first man in the world to watch the blood circulating along the capillaries. He watched it in a cocks comb, in a rabbit's ear, in a bat's wing, in a .tadpole's tail, and he waxes enthusiastic over what he saw in the last:

"A sight presented itself more delightful than any my eyes had ever beheld, for here I discovered more than fifty circulations of the blood in different places. I saw that not only the blood in many places was conveyed through exceedingly minute vessels from the middle of the tail towards the edges, but that each of the vessels had a curve, or turning, and carried the blood back towards the middle of the tail in order to be conveyed to the heart.

"Hereby it appeared plainly to me that the blood vessels I now saw in this animal, which bear the names of arteries and veins, are in fact one and the same—that is to say, they are properly termed arteries so long as they convey blood to the farthest extremities of its vessels and veins when they bring it back towards the heart." Well might' Leeuwenhoek grow If f enthusiastic, for he hid *een one of the IjT most wonderful sights that the eyes of a man can behold.

: i lj;