Page:Popular Science Monthly Volume 88.djvu/198

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Popular Science Monthly

A Boy's Street Boat

ECHOING the spirit of his fore-fathers who crossed the bleak prairies of the west in the days of the California gold rush, when sails were occasionally raised on the prairie schooners to help the horses along, a New York boy has added a leg o' mutton sail to the foot power driving equipment of his "scooter" with the result that he has been several times in danger of breaking the speed laws of his city.

With front and rear wheels oiled well,

With the aid of a brisk breeze, this scooter can break the city's speed laws

and a brisk breeze blowing, he can travel at a twenty-mile-an-hour clip without much difficulty, despite the crude construction of his vehicle. The front wheels are those of a discarded baby carriage, while those in the rear are rollers taken from skates. The name of this conveyance is the "windmobile," which is at least as happy as the names of apartment houses and Pullman cars.


Bread Without Grain Flour

CHEMISTRY in Germany is struggling to produce a substitute for grain flour in making a palatable and nourishing bread. The recent potato harvest being large, most research-workers have sought to use flour from grain in place of potato starch. The difficulty is that when bread contains an unusual proportion of potato starch, or even of rice or tapioca starch, it lacks the sponginess produced in ordinary bread through the carbonic acid developed by the fermentation of yeast or by baking powder.

In an article on the subject in Umschau some account is given of the experiments made to overcome the objections to the use of grain flour substituted. It had been proved that the defect in pure starch flour for bread-making is the lack of gluten, for the elasticity and toughness of ordinary dough are caused by the albumen contained in gluten. A chemist named Fornet claims to have found a substance which, when mixed with dough from starch flour, produces the physical characteristics of gluten. The dough is raised with yeast, can be made from all kinds of starch, and looks like ordinary white bread. The bread has been found edible at the army front when several days old. The substance discovered is not yet announced. The famous chemist, Wilhelm Ostwald, has proved that the albumen of gluten is coagulated by heat during baking and has used Gigg albumen instead with or without a gas-producer, as yeast or baking powder, with good results, but the process is too costly. Walter Ostwald and A. Riedel have substituted thick starch pastes for the various albumens in the dough. These pastes resemble gluten in the qualities of elasticity and impermeability to gas and are also cheap. The leaven is made of potato flour, milk, and pressed hops; baking powder can also be used. The inner friction of the starch paste produces in baking the necessary puffiness and porosity of the dough, and the loaf shows an elastic, porous crumb of fairly normal thickness.

Wilhelm Ostwald also substituted casein dissolved in ammonium carbonate for gluten. In baking, the ammonia and carbonic gases present acted as leaven while the casein replaced the gluten of ordinary white flour.