Section D. 



PRESIDENTIAL ADDRESS: 



Bv Lt.-Col. H. Watkins-Pitchford, F.R.C.V.S., F.R.S.E. 



Our section comprises a field so broad, and embraces such widely- 

 sundered lines of scientific thought, that it is obvious that one indi- 

 vidual — though he may have the hardihood to preside over such a 

 Section — cannot pretend to more than a superficial knowledge of the 

 majority of subjects included therein. 



I shall, therefore, confine my remarks to one small corner of 

 my own special subject — Bacteriology — knowing that even by so 

 narrowing down my horizon, I shall frequently be (5onfronted with 

 the unexplored and unknown, and at best be able to throw but a 

 feeble ray of light upon a subject, in which all South Africans must 

 be more or less interested. 



The Horse, with its congener the Mule or Ass, has been bound 

 up with the progress of Man from remote times, and, a moment's 

 reflection will sufiice to show that he is still indispensable to us in our 

 pursuance of the arts of Peace or in the successful waging of War. 



The welfare of the horse, and the suppression of a horse- 

 disease, which has almost extinguished the species in vast tracts of 

 our Continent towards the Equator, constitutes a question to which 

 none of us can feel indifferent ; involving as it does a problem 

 nearly related to the prosperity, both economical and social, of the 

 land in which we live. We know from the records of the Cape 

 Colony, that this equine scourge troubled the early settlers of 1709, 

 as much as it does the South African of 1907. It will suffice to 

 mention the theories held in early times concerning the causation of 

 the disease, namely : cold, dew, miasma, cobweb, the precipitation 

 of pathogenic spores from high altitudes, the gummy exudate 

 from our indigenous thorn or mimosa trees, mists, and winds 

 from certain points of the compass, and many other ideas. 

 It is, of course, easy to argue from the cause to the effect when 

 the former has been established, but it always struck me as strange 

 that amid so many theories and speculations, the parallel of the 

 Malarial disease of Man had escaped application to horse-sickness. 

 Both are essentially paludal or marshy diseases, and the conditions 

 favourable to the spread of one, must always have been concerned 

 in the manifestations of the other disease. 



Shortly after coming to this country, in 1896, I suggested in 

 some of my earlier observations the parallel between malaria and 

 horse-sickness, and attempted to apply the comparison to the solution 

 of the question of the cause of the latter disease. 



