Page:Sir William Petty - A Study in English Economic Literature - 1894.djvu/48

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Tractate on Education and the Bills of Mortality.
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the growth of London. This is substantiated by the increase in deaths in healthful years, or in years in which there was no plague. The town is gradually moving westward. The King's Court is at Westminster. The narrow streets of the city are not adapted to increased traffic. The crowding of buildings within the walls has caused people to build new ones outside. Chapter ix contains his favorite argument for the equalization of parishes. It would be more economical and would offer a better division for poor relief. In the next chapter he notices the exaggerated notions of the size of London. It was believed that six or seven million souls might be the true number. Only one in four hundred would die yearly if this were so. How can we estimate the population exactly? To get the result 384,000, which he offers as the true number, he uses three different methods; all are conjectural. In the first method, from the christening list is deduced the number of mothers, and from these the number of families; finally, by allowing eight persons in each family, the total population. A table of mortality by decades, constructed by guess-work, is fitly followed by the astounding statement that London doubles its population in eight years. In chapter xii, with information supplied by lists from a country parish, he reaffirms what he has already said in regard to the population of the two sexes, giving the ratio as fifteen females to sixteen males. Whatever else he finds in them only confirms what the study of the London Bills has lead him to adopt. He brings the work to a close by again insisting on the usefulness of such inquiries. Many spend their time uselessly in trying to make gold. The result of such efforts,