value. In one case the Supreme Court of Illinois, acting under a statute which required all land to be assessed at its full and fair value, corrected an assessment of railroad property conceded to be at only one-third its value, as being too high, on proof that the average assessment of other lands in the county was at only one-fifth of their value. And in the city of Chicago in the ten years from 1871 to 1881 assessments of aggregate values of real and personal property declined for the whole city by two-thirds, whereas the actual values nearly doubled.

So in the empire of France prior to the war of Napoleon III. against Germany ending in Sedan, the published statistics of the French army called for 1,400,000, whereas only between 400,000 and 500,000 men were in the service.

Again, in the debates on the slavery issue, preceding the war of the rebellion, Mr. Toombs and other Southern senators cited the small returns of pauperism in the Southern States against the large returns in Massachusetts as evidence of the greater wealth of the Southern States. To this it was replied that returns of pauperism measured only the extent of the state provision for the relief of the poor, and not the extent of the poverty. A state might escape all statistical appearance of pauperism by making no provision whatever for its poor.

12. The Results of Statistics.-The difference in certainty between the a priori and the historical method will appear by contrasting the perfect blank to which the mind of any a priori reasoner would be reduced if asked to say how many bachelors in France would marry single women in any given five years; or how many would marry widows; how many widowers would marry spinsters, and how many widowers would marry widows. But let any child of fifteen years of age be told what the actual proportion was in the three following periods, of five years each, and he could instantly answer the inquiry for any future period within a narrow margin. The proportions were:*

Any person glancing at this table could safely predict that in the five years from 1880 to 1886 in France the marriages of single

*"Condition of Nations," p. 27.

MARRIAGES AND HEALTH.

31

men to single women would be between 8,300 and 8,400, that the marriages of bachelors with widows would not vary 50 from 350, that the marriages of widowers with spinsters would be within 50 of 950, and that the marriages of widowers with widows would be between 315 and 350.

Still more difficult would it be on any a priori basis to determine how many men under thirty years of age or under fortyfive will marry women of over 60 years of age in Belgium. The case comes entirely within our reach, when we learn that in the six following periods of five years each, women of over 60 married men of the ages here given :*

13. Utility of Statistics.-The national utility of such statistics may be illustrated by the fact that the belief once widely prevailed that people subjected continuously to an enervating climate became "acclimated," so that it affected them less than those newly brought under its influences. If this were true it would be the policy of the British government to continue troops permanently at whatever post they were sent to. If the reverse were true it ought to change them frequently. Statistics were collected of past experience, and it was found that the mortality was twice as great among those continuously subjected to the strain of a bad climate as in those exposed off and on, or, in effect, that the longer the human frame was exposed to injurious conditions the less was its power of resistance. Hence the government ordered that no troops should be stationed in distant colonies more than three years. The result was that the average annual mortality of British troops serving abroad, which had been previously 48.58 in 1,000, was, subsequently to the order, 24.2, a reduction of one-half.

In certain cases statistics relating to health point the way to investigations concerning the causes of diseases as related to either climate, diet, water, or hygiene of particular districts with irresistible force. Thus in France, out of 100,000 recruits in one department of the Pas de Calais, only 118 had to be exempted from

*"Condition of Nations," p. 27.

cause.

service for scrofula. In another department immediately contiguous (du Nord) 2,809 out of 100,000 were exempted for the same One department contained not one case requiring dismissal for glandular disease, another contained 8,832 in 100,000. In one only 36 in 100,000 were incapacitated through loss of teeth, in another 6,700.

14. Regularity of Phenomena Shown by Statistics.— Accidents in coal mines are so regular that in England the production of 89,419 tons of coal costs a life, in Germany the production of 70,461. Among the miners of Frieburg 1 man and 12 women in 10,000 reach the age of 90 years. Among the general laborers 10 men and 26 women out of 10,000 reach the same age. Relief from all work by retirement from business tends to shorten life and brings it below that of the peasant. Statistics also show many forms of peculiar natural compensation, as that years of great epidemics will be followed by years of so much less than the usual number of deaths, and with such an increase of births as to nearly restore the population to what it would have been without the epidemic.

One of the most important facts disclosed by statistics is the constancy of the ratio which crime, and other forms of action which are believed to rest on perfect freedom of the individual, will bear to society and to certain of its conditions, especially illiteracy and destitution. In Great Britain* the record of coroners' inquests for the three years 1865, 1866, and 1867, shows a constancy in crime like or exceeding that which pertains to the revenue or to any department of production.

15. Statistics Taken With a Bias.-Statistics have been extensively taken in most countries to show the proportion which crime bears to illiteracy, to particular forms of religious faith, or to intemperance, while in very few cases are we able to learn the degree in which crime results from poverty. It is important that those who have charge of collecting statistics for governments should be without bias or theory as to what the statistics ought to prove. While in ordinary years in Ireland the arrests for crime are only from 4,000 to 5,000, in 1849, the culmination of the famine, they rose to 41,989, from which they fell to 11,788 in 1854, simultaneously with a fall in the number of ejectments of small householders from 74,171 in 1850 to 8,989 in 1854, to 4,972 in 1862, 311 in 1869, and 444 in 1870. Again in Cis-Leithania (Austria) in 1871 out of 22,620 persons convicted of crimes, 18,820 were utterly destitute, 2,637 were on the verge of destitution, and only 163 were well-to-do.

It results in errors of inference also, in the treatment of statistics, both in politics and economics, to display abnormal industry in collecting the facts which are supposed to be the effects of a particular cause, and to make no statistical or other research which might develop other causes not recognized, or show a greater relative power in them than in the one cause assumed.

For instance, Helper's "Impending Crisis" displayed with great fullness the superiority of the productive industries of the Northern States over those of the Southern, leaving it to be inferred that this superiority was wholly due to the relative conditions of the laborer of the two sections as being the one free and the other enslaved. It made no account of the difference, in quality and productive value, between a population wholly European, inheritors of thirty centuries of civilization, and a population, forty per cent. of which was African, inheritors of but three centuries of civilizing influence. Here the statistics might all be true, but the inference might require to be modified by other statistics showing the relative productive value of newly civilized races compared with those among whom habits of production had been longer inherited. Nott and Gliddon, in their work on "Types of Mankind," had presented historical data tending to show the primeval and perpetual inequality of the two races, white and black,

leaving it to be inferred that this inequality necessarily justified slavery. The historical data might be correct, and the inference exaggerated.

So Mr. H. F. Redfield published a careful collection of statistics showing that in the twenty years after the war of 1861-5, upwards of forty thousand homicides were committed in the Southern States, that a very large proportion of them went unpunished, and that the ratio of homicides to population was several times greater than in the Northern States. The inference appeared to be that the Federal Government, whose police powers were so imperfectly developed that it was powerless to prevent the assassination of two of its presidents, should exercise police jurisdiction either throughout the South or throughout the Union. It was thus assumed that the ratio of murders would be equalized by bringing the two sections under one administration of law. This again overlooked the fact that one of these sections was almost wholly of one race, while the other was divided nearly equally as respects numbers between two races, between which marriage was repugnant, and social equality and sympathy practically impossible. No observant person can have any reasonable doubt that an introduction into any one northern state, of an alien race to the extent of forty per cent. of the whole, too unlike the existing to intermarry or associate, would be strenuously opposed on all sides, and if permitted would greatly increase the rate of homicide.

The necessity of collecting duties on imports leads also to the collection of very full statistics of imports and exports in most countries,* while so far as the internal trade remains

*W. Stanley Jevons ("Theory of Political Economy," p. 23), says: "I do not hesitate to say, too, that economics might be gradually erected into an exact science if only commercial statistics were far more complete and accurate than they are at present, so that the formulæ could be endowed with exact meaning by the aid of numerical data. These data would consist chiefly in accurate accounts of the quantities of goods possessed and consumed by the community, and the prices at which they are exchanged. There is no reason whatever why we should not have those statistics, except the cost and trouble of collecting them, and the unwillingness of persons to afford information. The quantities themselves to be measured and registered are most concrete and precise. In a few cases we already have information approximating to completeness, as when a commodity like tea, sugar, coffee, or tobacco is wholly imported. But when articles are untaxed and partly produced within the country, we have yet the vaguest notions of the quantities consumed., Some slight success is now at last attending the efforts to gather agricultural statistics; and the great need felt by men engaged in the cotton and other trades to obtain accurate accounts of stocks, imports, and consumption will probably lead to the publication of far more complete information than we have hitherto enjoyed. The deductive science of economics must be verified and rendered useful by the purely empirical science of statistics. Theory must be invested with the reality and life of fact."