Labor's Codperative Policy 169 
law’ strikes of railway switchmen and yardmen and 
the strike of the anthracite miners; in the year follow- 
ing, a strike of the marine workers in all principal 
ports and conflicts in the clothing, building and pack- 
ing industry; and in 1922, when the number of re- 
ported strikers rose to 1,600,000, there took place 
the great strikes of the coal miners and of the rail- 
road shopmen.” 
So in the very years of the long bull market, a new 
era of comparatively peaceful relations between 
Capital and Labor helped the average of stock 
prices to achieve its new plateau. 
Human Engineering 
Along with these more peaceful relations have 
come feats of “human engineering” which have cut 
sick days among the workers, and shown that peri- 
odical physical examinations pay dividends to owners 
and health to workers. Employers and employees 
alike profit by mutual benefit arrangements adopted 
by the big corporations. Group insurance made pos- 
sible by employers contributing dollar for dollar with 
the employed has helped reduce the national sick 
bill and increased general prosperity. 
Harold A. Ley, President of the Life Extension 
Institute, reports a reduction of eighteen per cent 
in mortality in a group of policyholders taking a 
health service, now standardized under a mutual 
benefit plan that has been adopted by many great 
corporations. 
A study by Doctor A. H. Ryan, of Tufts College,