Decembek 20, 1895.] 



SCIENCE. 



829 



It might be claimed that this constancy 

 of ratio of distribution of casualties among 

 the four classes is only a reflection of the 

 constancy of the ratio of the numbers of 

 those classes. It will t)e noted, however, 

 that in the case of only two of them can 

 anything be known of that ratio and, in- 

 deed, in these two only can it be anything 

 like constant. Travelers on the public high- 

 way and trespassers can only come into the 

 enumeration when they become victims of 

 casualty. 



An examination of the detailed figures as 

 shown in Table A is instructive, as bearing 

 on this question. Consider, for example, 

 the two classes, impossible to enumerate in 

 total, referred to above. The percentage of 

 the total number of casualties affecting 

 travelers on the highway does not varj^ 

 greatly in the two years 1891 and 1892, be- 

 ing 5 % in 1891 and 5.9 % in 1892. The 

 actual number of casualties, however, was 

 190 in 1891 and 239 in 1892, a variation of 



over 25 % . Is there- any reason for assum- 

 ing that more travelers on the highway 

 were exposed to injury in 1892 than in 1891? 

 In 1892 the number of persons injured was 

 700 greater than in 1891. If the method of 

 investigation now begun be maintained for 

 a sufficient length of time, causes for such 

 variations in the total and in the distribu- 

 tion will undoubtedly be discovered. What- 

 ever might have been the cause, in the pres- 

 ent instance, of the increased number of 

 casualties, it looks very much as if the in- 

 creased vigilance exercised over the safety 

 of passengers had shunted a part of the 

 hazard over to the employes and travelers 

 on the public highway, although there is no 

 marked increase of percentage in either 

 case. The matter might be put in this 

 waj': Seven hundred more people will be 

 injured this year than last ; employes and 

 travelers on the highway will get a little 

 more than their share of the increase, be- 

 cause the corporation is going to take a lit- 



Table B. — Classified as to Nature of Injury. 



Death 



Loss of limb 



Loss of finger or toe.... 



Spinal injury 



Fracture or dislocation. 



Sprains 



Cuts and bruises 



Miscellaneous 



NUIIBER OF CAStTALTIES. 



348 

 90 



101 

 15 



225 



369 

 1523 



720 



366 

 90 



121 

 51 



269 



426 

 1913 



811 



105 

 105 

 268 

 362 

 1893 

 836 



266 

 71 

 79 

 21 



194 



411 

 1134 



918 



330 



84 

 102 



48 

 239 

 392 

 1615 

 821 



EATIO OF DISTRIBUTION. 



1891. 



% 

 10.3 



2.7 



3.0 

 .4 



6.6 

 10.9 

 44.9 

 21.2 



1892. 



% 



9.0 



2.2 



3.0 



1.3 



6.6 



10.5 



47.2 



20.2 



8.5 

 2.1 

 2.7 

 2.7 

 6.6 

 9.1 

 47.4 

 20.9 



1894. 



% 



8.6 



2.3 



2.6 



.6 



6.2 



13.5 



36.6 



29.6 



Mean. 



~w~ 



9.1 



2.3 



2.8 



1.3 



6.5 



11.0 



44.0 



23.0 



Fig. 7. 



Fig. 8. 



1. Death. 



2. Loss of limb. 



3. Loss o£ finger or toe. 



4. Spinal injury. 



RESULTS. 



5. Fracture or dislocation. 



6. Sprains. 



7. Cuts and bruises. 



8. Miscellaneous. 



