# Page:Popular Science Monthly Volume 90.djvu/692

676

��Popular Science Monthly

��vertical position by means of rings and clarhps screwed into a tall post in such a manner that it can rotate freely. Its height can also be adjusted so that a fixed point on the rod is at the level of the observer's eye. In using the apparatus, the observer sta- tions himself in such a position that the cloud selected for observation is seen in the same straight line as the central spike. He then turns the cross-piece until the cloud appears to travel along the line of spikes, while he remains motion- less. The cross- piece will then be parallel to the line of motion of the cloud, and the direction in which it points can be read off on a graduated cir- cle which is fixed to the rod. The rod may be turn- ed by an observer standing at some distance away from it by means of two cords tied to a second short- er cross-piece at- tached to its lower extremity.

The observer notes the time the cloud takes to pass from spike to spike. The dis- tance between two spikes is known, and also the altitude of the cross-piece above the ob-.

server's eye. A rudimentary knowledge of geometry tells us that the ratio of the latter distance to the former is the same as the ratio of the cloud's altitude to the actual distance it travels in apparently passing from one spike to the next. The altitude of the cloud may be assumed to be the average altitude for a cloud of its type.

The nephometer, shown in another p^- ture, is used to determine "degree of cloud- iness," or relative area of the sky covered by clouds.

���The observer is sighting the image of a cloud reflected into the mirror from an artificial pool of water below the window, to determine its height

��What Is a Man ? Break a Thousand Eggs and You'll Have His Contents

WHAT is a man? How much is he worth from a scientific viewpoint? According to one way of looking at it a man is worth about \$2.50 a day from his shoulders down and anywhere from \$50,000 to \$1,000,000 a year from his shoulders up. This may be said to be the estimate of the average successful business man.

The scientist, however, looks at the question from another angle. According to him a man is worth \$2.45 for illumi- nating purposes, since a man weighing 150 pounds contains about 3,500 cubic feet of oxygen, hydrogen and ni- trogen in his con- stitution, which at seventy cents per 1 ,000 cubic feet equals the price above. Also a man contains enough carbon to make 9,360 lead pencils; enough phosphorus to make 800,000 matches or enough to kill 500 persons, and enough water to fill a thirty-eight quart reservoir.

Furthermore, it makes no dif- ference how sour a man may look he contains about sixty lumps of sugar, a great deal of starch, chloride of potash, magnesium, sulphur and hydrochloric acid in his system. There are fifty grains of iron in the blood of an ordinary man, enough to make one spike large enough to hold his weight.

What, is a man? This is the sbmewhat cynical answer of one scientific man:

"Break the shells of 1,000 eggs into a huge pan or basin and you have ingre- dients from which to form him from his toe nails to the most delicate tissues of his brain . ' '

�� �