550 Our Surroundings 



tremendous cost in human life and labor. Most of the people in 

 those days were poorly housed, with living conditions far from 

 sanitary. Today modern science has revolutionized building, 

 making it possible to erect with astounding speed safe, attractive, 

 sanitary buildings well adapted to our various needs. 



Science has developed improved methods of quarrying, cutting, 

 and polishing building stone, of making brick, and of shaping 

 lumber. Science has given us concrete and steel to build with 

 two materials largely responsible for our tall buildings, great fac- 

 tories, bridges, dams, and roadways. 



By means of labor-saving devices, such as the steam shovel, the 

 power derrick, and the automatic riveter, Science has enormously 

 reduced hand labor and speeded up construction. 



By the development of proper heating, ventilating, and plumb- 

 ing systems, Science has safeguarded health and assured not only 

 comfortable working conditions in our offices and work shops, but 

 also increasingly comfortable homes. 



Science and Industry. From the dawn of civilization until 

 a century ago, industry progressed very slowly. In the early days, 

 the members of each family made by hand their crude tools, their 

 shelter, their clothes, and their furniture. With the growth of 

 town and city came specialists, such as the carpenter, the tailor, 

 and the shoemaker, but poor tools limited their output and they 

 usually served only their own community. 



When Science gave to man the stationary steam engine and 

 the railroad, manufacturing progress became rapid. Machines 

 were invented which quickly and efficiently do the work formerly 

 done laboriously by hand. One man can now do the work of 

 the many in former days. Moreover, railways now bring raw 

 materials from a distance and carry away manufactured goods, 

 thereby speeding up industry and extending the markets. 



The discoveries in electricity and the invention of dynamos 

 and electric motors have still further helped industry, for the 

 power of distant waterfalls, formerly going to waste, is now trans- 

 formed into electricity, transmitted hundreds of miles by wire, 

 and used in motors to drive machinery with greater economy than 

 by the use of steam. 



