Page:Popular Science Monthly Volume 48.djvu/783

Rh that unlike magnetic poles mutually attract, he invented several forms of compass, including the first which could be constantly used to steer by as the modern mariner's compass is used, and he proposed the first magnetic (electric) motor. Columbus figures in Mr. Benjamin's history as discovering the line of no variation of the compass needle. After him comes Hartmann, who discovered the dip of the needle, then Sarpi, whom Galileo addresses as "my father and my master," Porta, Cardano, and other learned Italian physicians of the sixteenth century. These men prepared the way for the important advances made by Queen Elizabeth's physician William Gilbert, who is rightly regarded as the founder of the science of electricity, even if Francis Bacon could never appreciate his talents. The young science was fostered by Galileo and Descartes and von Guericke and the Abbé Nollet on the Continent, by Newton and Boyle and Hauksbee in England. Other men, also, less known to fame, were at work upon electrical problems during the same period. Gilbert's discoveries did not fail to raise up a swarm of charlatans, among whom Van Helmont and Kenelm Digby stand forth prominently. The history stops with Franklin's demonstration that lightning and electricity are identical. This, says Mr. Benjamin, "brings to culmination the long series of events whereby the single incomprehensible effect observed in the lodestone and the amber gradually grew into recognition as a world force, subject to universal law and pervading all Nature." The volume is tasteful as to its mechanical features, and is embellished by reproductions of many of the portraits and quaint engravings in the early books from which its material has been drawn.

Those who are desirous of improving the environment of the poor may obtain valuable guidance from the eighth special report of the United States Commissioner of Labor. As would be expected, the greater part of the report is devoted to model dwellings, other matters receiving some consideration in the fore part of the volume. Dr. Gould tells what is being done to secure better housing for the poor in New York, the chief cities of Great Britain, and more briefly in western Europe, through building and sanitary laws, and municipal condemnation of insanitary houses. Sanitary aid societies have greatly furthered this end by co-operating with or spurring on the public authorities in their work. A form of private effort that has done much good is the rent-collecting agency of Miss Octavia Hill, in London. The method pursued by her and the assistants whom she has trained is both businesslike and philanthropic. She buys tenement houses with capital furnished by those interested in her work, and undertakes the collection of rents or the whole management of buildings for others, at fixed rates. She rewards prompt payments and proper use of the premises by making repairs and improvements in the buildings. The incorrigible are turned out, but by the use of tact the number of these is kept very small. The moral influence of her system has been to admit women to a greater extent into the management of housing companies. In his account of model buildings Dr. Gould takes up successively "block buildings" or flats, small houses, and lodging houses. He describes model block buildings in Brooklyn, New York, and Boston, and in large cities of Great Britain,