256 THE POPULAR SCIENCE MONTHLY. 



This epidemic was clearly the same as that which, had prevailed, 

 with somewhat of the same severity, not only in this country, but also 

 over the greater part of the Continent of Europe, two years pre- 

 viously ; and hence there can be little doubt that the high rate of 

 mortality by which it was everywhere characterized must have been 

 due to general rather than to local causes. It had the good effect of 

 frightening many of our local health authorities into a more efficient 

 observance of their duty in regard to vaccination ; and the result has 

 been that, during the last two years, the rejjorts of the Registrar- 

 General show an almost complete extinction of small-pox in the nine- 

 teen great towns, whose aggregate population (about three and three 

 quarter millions) equals that of the metropolis. The fresh outbreak 

 which has taken place during the first half of the present year has 

 been almost entirely restricted to the London area, and evidently 

 points to the imj)ortance of a more strict enforcement of the vaccina- 

 tion law, which is at present rendered nugatory, as regards no incon- 

 siderable proportion of the metropolitan population, by the migration 

 of families from one district to another. 



The prolonged experience of Dr. Martin, in regard to the facility 

 of keeping up heifer-vaccination continuously from the original stock, 

 altogether confirmatory as it is of what has been reported on this sub- 

 ject from France, Belgium, and St. Petersburg, seems to me to justify 

 the demand that our Government should maintain the requisite estab- 

 lishment on a sufficient scale to meet the requirements of the whole 

 country, so that every vaccination and revaccination may be per- 

 formed (if desired) with lymph derived from the original cow-stock, 

 without any humanization whatever.* The vaccinia of Jenner may 

 be thus maintained in its original efficacy, without the impairment of 

 its protective influence by prolonged "cultivation" in the human sub- 

 ject, and thus only can it be secured against the contaminating influ- 

 ence of human disease, the liability to which furnishes the anti-vacci- 

 nationists with their strongest weapon. 



No benefit can be reasonably expected from the adoption of any 

 system which is based on the induction of vaccinia in a calf or 



resemblance to the " Black Death " that carried off what was estimated at one third of 

 the population of Europe in the fourteenth century, as to suggest that the latter may 

 have been really a peculiarly malignant small-pox. My friends greatly regretted the want 

 in the United States of a system of " compulsory " vaccination ; but said that, when out- 

 breaks of small-pox occurred in their towns, the municipal authorities took the matter in 

 hand, and insisted on the immediate vaccination and revaccination of all dwellers in the 

 infected localities, by which means these outbreaks were brought under control. As there 

 is no registration system in the American Union, I could not obtain any definite informa- 

 tion as to the amount of its small-pox mortality; but no one seemed to entertain the 

 least doubt as to the preventive efficacy of vaccination. 



* I am assured by Dr. Martin that vaccination with heifer-lymph dried on ivory 

 " points " succeeds in as large a proportion of cases as vaccination with fresh human 

 lymph, provided that it be practiced according to the method which his large experience 

 has led him to adopt as the most effective. 



