Dr. Mi'KRAY on Vaccination. 337 



Mr. Wliewell, in liin late leseavclies on this subject, and they 

 earnestly invile commnniralions on this head from any residents 

 at lliose ports who may have leisnre and talvc interest enougii 

 in the important questions connected with the subject. 



Cape Town, Port Elizabeth, 



Simon's Bay, Knysna, 



Saldaidia Bay. 

 Ascension, , Tristan d'Acunlia, 



Mauritius, Madagascar, 



Mozambique. 



In Cape Town and Simon's Bay, they have the pleasure to 

 report, that a scries of observations, under the superintendence 

 of Captain Bance and Mr. Levien, have already been under- 

 taken at the instance of the Astionoiner Royal, and are now in 

 active progress. 



0» VA C C IN A TION. 

 By Dr. MURRAY. 



[Rend nl the South African Literary Tnstifutiov.] 



As no Scientific Investigation ought to be foreign to the IVFem- 

 bcrs of ibis Institution, I would beg to call their attention to 

 the snbject of Vaccination, which is one of such very great 

 importance to the community, that every plausible suggestion 

 tending to perfect our knowledge and practice of it, should be 

 taken into consideration. 



I need scarcely mention what must be well known to you all, 

 (hat of late it has rather got into discredit, from having been 

 found to fail in affording universal and absolute protection 

 against the contagion of Small-Po.^ ; and that, although some 

 of the causes which operate to prevent its full anlivariolons 

 effect on the constitution have been discovered and pointed out, 

 there are others which seem not to be perfectly understood, for 

 many of those persons who have passed through the Vaccine- 

 Po.\ apparently in a regular manner, and under circumstances 

 that have been considered favoinnble, have, nevertheless, suf- 

 fered afterwards, more or less, from Small Po.v, when exposed 

 to the influence of its contagion; and hence it is inferred, that 

 some important cause or causes of its failure still remain to be 

 ascertained. 



Twenty years ago, Cases of Sniall-Po.x after Vaccination 

 were comparatively rare, and indeed the possil)ility of the 

 occurrence was scarcely cr(ulited or admitted ; but since that 

 period it has been fully provf:d and acknow ltt!<.';cd ; and, 



•2 u 



