Page:Popular Science Monthly Volume 90.djvu/341

 Popular Science Monthly

��325

���© Underwood and Underwood

Bridgeport school children going through a tooth-brush drill. Thousands of school children and adults in other cities are now given a regular drill in the care of their teeth

��The Tooth-Brush Drill Has Become a Part of the School Course

DECAYED teeth are causing more harm to the human race than alcohol. Dr. Alfred C. Fones, of Bridgeport, Conn., says that approximately ninety-five millions of persons in the United States have decayed teeth. Dentistry's next great step, in his opinion, is to wipe out or prevent tooth decay by a systematic campaign of educa- tion on the care of the teeth among school children.

How shall this be done? Bridgeport's plan has attracted wide attention already. Every child in that city submits to a thorough examina- tion of the mouth and is given free treatment. This type of clinic costs about eighty cents per child per year. The city assumes one half the respon- sibility in educating and helping the children to preserve their teeth. The other half, which is placed on the child and its parents, con- sists in providing proper food and in caring for the mouth.

Decayed teeth are due to the action of acids on the teeth, followed by the work of micro-organisms flourishing in the remains of food. To combat decay the surface of the teeth must be kept absolutely clean and free from deposits and accretions.

���The scissors-grinding machine run by dog power. Nothing less than a full day's work .with a half hour's sleep at noon satisfies Rover

��Operating a Scissors Sharpener by Dog-Power

TH E itinerant tradesman, umbrella mender and scissors sharpener are familiar figures in the suburbs and on the outskirts of large cities, where they break the silence and the monotony of the hours with their horns. But in the rural districts the companion of such vendors is usually a dog of nondescript type.

That the dog may be made a useful member of the firm has been proven by a man who travels through Carpenteria, Cal., soliciting scissors-grinding trade. He has a machine for the work and the dog has been taught to fur- nish the power for it. This he does right merrily. He gets on the wheel of his own accord and treads away with vigor, while his master sharpens scissors and knives. To all appearances the dog thinks it is a game devised for his amusement; but the owner believes that a sense of re- sponsibility and a desire to do a full share of the work of the day is stronger than the play spirit in his companion.

When business is slack the animal will run to his wheel and bark reproachfully at his master until the man feels obliged to attach the rope which turns the grinder.

�� �