July 22, 1887.] 



SCIENCE. 



43 



portance of the discovery, whether for its practical utility or for its 

 application in general pathology." The committee investigated 

 ninety cases treated by Pasteur. Of this number, twenty-four had 

 been bitten on naked parts by undoubtedly rabid dogs, and the 

 wounds were not cauterized, nor otherwise treated in anyway likely 

 to have prevented the action of the virus. Of thirty-one that were 

 bitten, there was no clear evidence that the dogs were rabid, and in 

 others the bites had been inflicted through the clothes. It is esti- 

 mated, from experience of the results of bites in other cases.that, had 

 they not been inoculated, not less than eight among these ninety 

 persons would have died. Not one of them has shown since the 

 inoculation any signs of hydrophobia. The committee thinks it 

 certain that the inoculations practised by M. Pasteur have prevented 

 the occurrence of hydrophobia in a large proportion of those who, 

 if they had not been so inoculated, would have died of that disease. 

 And his discovery shows that it may become possible to arrest by 

 inoculation, even after infection, other diseases besides hydrophobia. 



If rabies be not reduced among the dogs of England, there 

 will always be a large number of persons who will require treat- 

 ment. The average annual number of deaths from hydrophobia 

 during the ten years ending 1885, was, in all England, 43; in 

 London alone, 8.5. These numbers may be taken as representing 

 only five per cent of the persons bitten, so that the preventive 

 treatment will be required for 860 persons in all England, and for 

 170 in London alone. 



In commenting on this report of the committee, the London 

 Lattcet says that " their verdict is the most important yet pro- 

 nounced upon the subject, and must go far to decide the 

 question of the prophylactic value of the inoculation of Pasteur. 

 The conclusion that the method has saved a considerable number 

 of lives, and that it is at present, and probably will be for long, the 

 only mode of saving from death those who have been bitten by a 

 rabid dog, affords strong support to Pasteur's conclusions, and, we 

 need hardly say, must have most important practical results." 



Measles. — The prevalence of measles in some parts of the 

 world, and its fatality, have aroused health-authorities to such an 

 appreciation of the necessity for restricting the spread of this 

 disease, that official steps are being taken for the attainment of this 

 end. A recent occurrence at Portsmouth, England, makes the 

 necessity for this work more emphatic. H. M. S. Crocodile arrived 

 at that place with forty persons sick with measles on board, who 

 were permitted to land. From these individuals the disease has 

 spread to an epidemic, and at last reports the number of deaths was 

 one hundred and ninety-seven. 



Leprosy in Louisiana. — Considerable excitement has been 

 occasioned in Louisiana by the report that leprosy existed at St. 

 Martinsville in that State. The State Board of Health has made 

 an examination, and finds that five persons are suffering from un- 

 doubted leprosy, while three others are as yet in doubt. 



BOOK -REVIEWS. 



Chance and Luck : a Discussion of the Laws of Luck, Coinci- 

 dences, Wagers, Lotteries, and the Fallacies of Gainblmg ; 

 •with Notes on Poker and Martingales. By RICHARD A. 

 Proctor. London, Longmans, Green, & Co. 

 The persistency of a superstition can generally be referred to the 

 subtleness and persuasiveness of the logic upon which it is founded, 

 or to the fact that it appeals to a strong instinct in human nature. 

 Doubtless both these influences have been at work in keeping alive, 

 among those in whom the hazarding instinct is at all strong, a fond- 

 ness towards a belief in their own favoritism, in the obscure forces 

 which control luck, and in the sundry other agencies which go to make 

 of chance something which is more than chance. For the benefit 

 of such, — and they form a respectable portion, both in size and 

 ability, of mankind, — Mr. Proctor has written this book. He hopes 

 to be able to convince a few of the errors of their ways, sadly recog- 

 nizing " that the gambling fraternity will continue to proclaim their 

 belief in luck, . . . and the community on whom they prey will, for 

 the most part, continue to submit to the process of plucking, in full 

 belief that they are on their way to fortune." 



The wide-spread belief in luck is in many ways easy to account 



for, and even to defend. There is an element of chance that enters 

 in the lives of every one of us ; and it is but natural that where this 

 chance favors the success of our projects, — though not the least 

 to our credit, — this should have a decided influence in the shaping 

 of our character. Much that is attributed to good fortune is really 

 good common sense and wise forethought ; but, allowing for that, as 

 long as there remains this element of uncertainty in our lives, it is 

 evident that there must be certain individuals who are lucky, in the 

 sense that they have been fortunate when they had no very 

 good reason to expect success, and certain others who have 

 been unlucky under the same circumstances. But this, Mr. 

 Proctor well insists, is a very different thing from the common 

 conception of a lucky individual, which regards such a man 

 as more likely to be fortunate in success depending entirely 

 on chance, in the future ; as a chosen being for whose benefit the 

 laws of probabilities will be suspended, and who can, even with 

 considerable confidence, count upon such benign intervention. It 

 is this conception that has the strongest hold upon gamblers, upon 

 the wisest and sharpest of them, as well as upon the people at 

 large, and is a very ridiculous and a very dangerous superstition. 

 If some way could be devised by which the expectation, the sub- 

 jective feeling of confidence, could be properly proportioned to the 

 mathematical chance of securing the desired prize, lotteries could 

 no longer exist, and the chance forms of gambling would appear as 

 utter folly. The methods by which such occupations are carried 

 on are devised to carefully prevent any such enlightenment, and 

 they easily succeed in so doing. 



The logic of the matter is very simple. Take lotteries as an ex- 

 ample. If ten persons each deposit five doflars, and agree that the 

 one throwing the highest number of points with a pair of dice shall 

 receive the fifty dollars, that would be a fair lottery. To test its 

 fairness, we have simply to consider, that, if one person bought all 

 ten deposits, he would be sure to win, and would neither lose nor 

 gain : in other words, mathematically the price to be paid for a share 

 in a lottery is obtained by dividing the amount that can be gained by 

 the number of shares. No lottery of this sort would pay : hence no 

 paying lottery is fair, and every lottery that exists pays those who 

 control it very well indeed. The Louisiana lottery, the peculiarity 

 of which Mr. Proctor characterizes as ' the calm admission, in aU 

 advertisements, that it is a gross and unmitigated swindle,' sells 

 monthly 100,000 tickets at five dollars each. Deducting from the 

 $500,000 thus received as much as $10,000 for expenses, and a simi- 

 lar amount for ' the charitable and educational purposes ' for which 

 the State sanctions the lottery, there remain $480,000. Instead of 

 distributing all this in prizes, they distribute only $265,000 ; and thus, 

 when all the tickets are sold, — and few are ever left, — the 

 managers have a clear profit of forty-five per cent per month. This 

 is exactly the same kind of swindling as would be committed by 

 the man who invited the ten persons to deposit their five dollars, 

 were he to give the one who threw the highest number of points 

 $26.50, and quietly pocket the $23.50 as a reward for his trouble. 

 Lotteries exist and pay, because people are willing to give 

 more for the chance of securing a prize than they ought to give. 

 They dwell frequently and long on the immensity of the prize, 

 entirely underestimating the slightness of the possibility of their 

 securing it, and thus cherish a sort of optimism which overlooks 

 barefaced robbery and tolerates the most glaring frauds. That 

 such is the case was experimentally demonstrated by the English 

 Government. Tickets for a lottery were offered for sale, not at a 

 fixed price, but for what they would fetch. The contractors bought 

 of the government tickets mathematically worth £\o at £1(3, and 

 again sold the tickets at a large advance. The public was perfecdy 

 willing, and actually asked, to be plundered. 



Gambling-banks and the superstitions of gamblers offer a still 

 more interesting topic. Here there is often much ingenuity dis- 

 played in arranging plans by which apparently fortunes must be 

 won, and in defending pet nodons with an array of apparently sound 

 argument. But the reason why a bank must win has often been 

 exposed. It is simply that it reserves for itself, under certain con- 

 ditions (apparently very unlikely), a certain sum, apparently small, 

 or it stakes a larger sum at exaggerated odds for the great proba- 

 bility of winning a small fee. Thus the refait in rouge et noir, 

 which apparently is a most improbable event, must, by the doctrine 



