The great proportion of crime in San Juan, as compared with the rest of the Island, is of course largely due to social conditions, inasmuch as it is the largest city in the Island and to a great extent the resort of undesirable characters for this reason. In the second place, as a coast town and the most important shipping and commercial center, it has a more or less shifting population, and a population composed to a great extent of an uneducated type among the working classes. Every seaport town offers opportunities for criminal classes which inland towns do not possess. The second town in the list, Rio Piedras, is the natural outlet between San Juan and the rest of the Island, which undoubtedly accounts for its large percentage of crime. The rest of the towns where crime is found in large proportion will be discovered to have a large floating population, people who are day laborers and who have no particular interest in the community, except as it provides them with an opportunity for earning daily wages. This class of population is always unfavorable to a community and is always to be found where large industries exist which employ a great number of men; and this is especially true when little attempt is made on the part of the employer to render the permanence of the job desirable by furnishing well-provided living facilities for the employee. It is noticeable that in Cabo Rojo, where the percentage of criminal cases is lowest, the population depends chiefly upon the hat-making industry for its support. This is added proof of the value of small industries from the point of view of community welfare. It is noteworthy that there was an immense increase in the number of crimes committed in the following districts: Ciales, where the number of cases increased from 431 in 1912 to 754 in 1915; Lares, where the increase was from 352 to 853; Vieques, where the increase was from 341 to 684; Yabucoa, where the increase was from 589 to 831; Yauco, where the increase was from 867 to 1,490. In the rest of the districts the number of crimes did not vary greatly from year to year, even decreasing in the case of Rio Piedras from 1,101 in 1912 to 911 in 1915. Of course, the difference in crime percentage might depend upon the efficiency of the police force or upon the severity of the Municipal Judge, but undoubtedly it will be found more often to depend upon local conditions such as strikes, or the introduction of large numbers of workingmen from another district to take part in agricultural or industrial work. The change of location and the resulting necessity of accommodation to local surroundings is apt to be dangerous to the morals of the individual.