EXACT METHODS IN SOCIOLOGY. 149 



of tlie present century. When Quetelet, in 1835, publislied liis 

 great work, Sur VHomme et le Developpement de ses Facultes, he 

 laid the foundation for a thorough statistical investigation of psy- 

 chological and sociological no less than of anatomical phenomena. 

 And after the publication, in 1846, of his work, Sur la Theorie des 

 Prohahilites appliquees aux Sciences morales et politiques, followed, 

 in 1848, by Du Systeme social et des Lois qui le regissent, there 

 was a rapid development of statistical methods in precision, and of 

 attempts to extend the statistical method to groups of facts which 

 had until then been studied only from a purely qualitative or, at 

 best, a vaguely comparative point of view. At the present time 

 every subdivision of descriptive sociology draws data from rich 

 collections of statistical materials, and employs statistical methods 

 for the further extension of knowledge. 



Thus, in the study of the social population, statistical methods 

 are employed not only to give the total number of inhabitants 

 dwelling within a given territory and the degree of density of 

 population per square mile, but also to show to what extent popu- 

 lation increases by births in excess of deaths, to what extent by 

 immigration in excess of emigration, and to what extent the com- 

 position of the population is rendered complex by the intermin- 

 gling of many nationalities. The character of a population, also, 

 and its social capacities are in a large measure statistically investi- 

 gated. General intelligence is studied by means of statistics of liter- 

 acy and illiteracy; industrial preferences by statistics of occupation; 

 habits of industry by statistics of the number in every thousand 

 of the total population who regularly follow gainful occupations; 

 frugality by statistics of savings, insurance, and home ownership; 

 and the amount of communication, whereby assimilation and co- 

 operation are rendered possible, by statistics of travel, mail, and 

 telegraphic service. 



Passing to that study of concerted feeling, thought, and pur- 

 pose which may be called a study of the social mind, and which 

 constitutes the second great division of descriptive sociology, we 

 find that it can be carried on, and that to a great extent it is prose- 

 cuted, by means of statistical research. 'We have statistics incom- 

 plete, but admitting of perfection, of those impulsive, emotional 

 disturbances of masses of men which take the form of strikes, insur- 

 rections, lynchings, and revivals. The report of the United States 

 Department of Labor on strikes, published in 1894, and a recently 

 published monograph by Dr. Frederick S. Hall on Sympathetic 

 Strikes, show the possibilities of this method whenever it shall be 

 exhaustively applied. It could be successfully applied to the other 

 phenomena mentioned. By painstaking effort and a sufficient ex- 



