150 Second Letter to Mr. Tilloch on the Cow-Vock. 



and their prejudices are strong, and not to be overcome by 

 reason. Hence, while the inoculation of the wealthy keeps 

 up a perpetual source of infection, those who either do not 

 choose, or cannot afford expense, are more exposed to this 

 distemper. The danger also is increased by the custom of 

 sending persons into the open air in every stage of the dis- 

 ease. Hence, while inoculation may be justlv esteemed as 

 one of the greatest improvements ever introduced into the 

 medical art, it occasions a greater sacrifice of life by what 

 has been distinguishexl by the appellation of the natural 

 small-pox." 



As a proof of this position, we have the following record 

 from a most diligent and careful observer of facts. Dr. Wil- 

 lan, in his account of the diseases in London. 



" A child having been inoculated in a court (whose 

 parent kept a chandler's-shop) consisting of twenty houses; 

 the consequence was, that in this court seventeen persons 

 took the natural small-pox, although the season was kind 

 (April) ; and eight of these died. 



"They in their turn became the focus of fresh infection, 

 and thus a private good was converted into a public evil." 



3. Description of the inoculated CoW'Pock. 



First, of the Pustule.'— 4th day, A rising pimple con- 

 taining a fluid ; the apex elevated. — 8th day, A circular 

 even-edged, flat, uniform pustule, containing a fluid in 

 cdls ; the apex a scab; circular inflammation. — 1 0th day. 

 Pustule enlarged with many small depressions; its central 

 part converting to a scab; fluid still transparent; the central 

 scab increased, and of a mahogany colour ; hardness and 

 circular inflammation. — 13th day, The central scab in- 

 creased in size, of a dark mahogany colour; the circle of 

 the pustule, as seen on the 1 0th day, completely converted 

 into a hazel-coloured scab; scarcely any fluid; inflammation 

 deadened. — 14th day, Almost all the pustule converted into 

 a hazel -coloured scab, surrounding the dark mahogany cen- 

 tral scab; scarce any containing fluid, and that only in the 

 circumference, which has lost its blue tinge, and looks 

 brown.r — 15th dav, The whole pustule converted into two 

 distinct scabs ; no fluid ; a white ring surrounding the pus- 

 tule from the peeling away of some dead cuticle. — l6th day. 

 More white concentric rings from the same cause, and the 

 baldness and inflanimation greatly subsided. 



These appearances may vary according to constitutions; 

 i\\ty werp drawn under piy eye, from examinations made on 



t^^Q 



