804. 



STATISTICS. 



understood, comprises two distinct inquiries, 

 the one relating to the individual facts which 

 form the materials for the calculation of aver- 

 age and extreme values, and the other re- 

 ferring to the averages and extremes them- 

 selves. This natural and convenient division 

 of the subject it is proposed now to adopt. 



1 . C)f facts considered as the elements of sta- 

 tistical inquiries. Scientific inquiries are con- 

 versant with two orders of facts : namely, 

 phenomena of varying intensity, and events 

 brought about by a multitude of causes. The 

 first class of facts enters very largely into the 

 science of physiology ; the last class consti- 

 tutes, though not to the exclusion of the first, 

 the mass of the materials by which the prac- 

 tical sciences of medicine and hygiene are 

 built up. 



As examples of phenomena of varying inten- 

 sity may be cited the pulse and respiration, 

 the temperature of the body, the secretions of 

 the skin, kidneys, and lungs, the evacuations 

 of the bowels, the weight and stature of the 

 body at different ages, and the muscular de- 

 velopment and power of different nations and 

 classes of persons. These phenomena, care- 

 fully observed and recorded by the aid of the 

 watch, the thermometer, the measure, the 

 balance, and other instruments adapted to 

 special purposes, become so many numerical 

 values, having the same relation to the aver- 

 ages deduced from them, as the more simple 

 events expressed in units bear to the mean 

 results for which they furnish the materials. 



As an example of an event brought about by 

 a multitude of causes may be mentioned the 

 event of death, governed, as to the age at 

 which it occurs, by original strength or pecu- 

 liarity of constitution, good or bad nursing 

 and management in infancy, sex, occupation 

 and habits of life, climate and place of abode, 

 skilful or unskilful treatment in sickness ; in 

 a word, by the varied influences which make 

 one man to differ physically from another. 

 This is an illustration taken from the science 

 of hygiene. The alternative of death or re- 

 covery from a disease induced by a cause or 

 causes of variable intensity in persons of 

 opposite sex and of different ages, with con- 

 stitutions modified by the several agencies 

 just specified, and submitted to different 

 modes of treatment, is an example from the 

 practice of medicine. Physiology furnishes 

 illustrations of the same kind in those func- 

 tions of the body (such as the cutting of the 

 teeth, and the first appearance and cessation 

 of the catamenia) which are dependent for 



of numbers as a necessary means of comparison in 

 this work of Achemval, led men to confound the in- 

 strument with the science. Dufau, in his Traite de 

 Statistique, incorrectly derives the term statistics 

 from the Latin status. 



The meaning attached to the words statism and 

 statist, in the writings of poets, essayists, and, 

 dramatists, bears out the view just put forward of 

 the proper signification of the term statistics. Mil- 

 ton, for instance, speaks of " statists and lawyers," 

 and elsewhere uses the term in the sense of a man 

 having political power and influence. Ford also 

 uses the word in this latter sense. South speaks of 

 persons who called our religion station. 



the period of their occurrence on peculiarity, 

 of constitution determined by the combined 

 action of the influences already adverted to. 



Between these two orders of facts phe- 

 nomena of varying intensity, and events 

 brought about by a multitude of causes 

 there is no other difference but that which is 

 apparent on the face of each, namely, that 

 each individual fact, in the one case, is repre- 

 sented by a variable number, while in the 

 other it is a simple unit. If, for example, we 

 count the pulse of several men at the same 

 age, we shall find that each separate observa- 

 tion gives a different number; but, the event 

 of death or recovery in cases of typhus fever 

 will be recorded as a simple unit. In all other 

 respects the two classes of facts closely re- 

 semble each other; for the number of beats 

 peculiar to the pulse of each individual, is as 

 much the result of the concurrent action of 

 several causes, as the event of death or reco- 

 very from fever. The original and acquired 

 constitution, towards the formation of which 

 so many causes must have conspired, deter- 

 mines the number of the pulse in the one 

 case, and influences the event of the disease 

 in the other. The two classes of facts are 

 also equally fitted to supply the elements for 

 the determination of average and extreme 

 values; for it is obvious that the mean and 

 extreme numbers of the pulse, in males and 

 females respectively, furnish as trustworthy 

 standards of comparison and data for reason- 

 ing, as the average number of men following 

 different occupations who die before any spe- 

 cified period of life, and the greatest age 

 which they respectively attain. 



From what has been just stated, it will be 

 seen that all the facts which form the mate- 

 rials for our averages, are phenomena or events 

 brought about by the concurrent action of a 

 multitude of causes. The facts or events 

 with which the physiologist and physician 

 are conversant, are remarkable for the mul- 

 tiplicity of the causes which conspire to pro- 

 duce them. The subject of study is the hu- 

 man frame, with its differences of sex, age, 

 and inherited or acquired constitution, acted 

 upon by the variable influences of climate, oc- 

 cupation, and habits of life, and still further 

 modified in disease by the treatment and re- 

 gimen which may happen to be adopted. In 

 consequence of the number and diversity of 

 the influences brought to bear upon it, the 

 human frame presents an object of study only 

 less difficult than the human mind, affected 

 by a like number and variety of moral causes, 

 of which the true nature and force have to 

 be unravelled by multiplied observations on 

 the condition of mankind under different cir- 

 cumstances ; the aggregate of such observ- 

 ations constituting a great part of the science 

 of statistics properly so called, and bearing to 

 the practical science of government the same 

 relation which pathology and therapeutics, 

 based upon large collections of facts, do to 

 the practice of medicine. 



Now this dependence of the individual facts 

 or events with which physiology and medicine 

 are conversant on the concurrent action of a 



