PATHOLOGY. G73 



influence of domestication than with young animals, and such as 

 are roaming at will in the open fields. Rarely, even in the best- 

 marked cases, have we more than a sectional portion of the 

 canal invaded ; in the horse this locality is variable, the large 

 intestine being rather more frequently the seat of the diseased 

 action than the small. Besides this variation as to exact situa- 

 tion, we may also observe that there are certain variations or 

 peculiarities exhibited in the manifestation and results of the 

 unnatural activities. In many the progress of events is ex- 

 tremely rapid, the termination fatal, with lesions of a very 

 attractive character ; in others, although the clinical phenomena 

 may not be very dissimilar, the course and termination are 

 delayed, while the tissue-changes are less distinctive and some- 

 times rather occult. 



For many years I have been forcibly impressed with the con- 

 viction that many cases — the greater number, indeed, which 

 terminate fatally with wonderful rapidity both in towns and 

 rural districts, and which are regularly regarded as enteritis — 

 are in many of their clinical features and post-mortem lesions 

 somewhat different from the conditions which in our day we 

 are inclined to accept as indicative of, or attendant upon, in- 

 flammatory action. In this opinion I am supported by other, 

 observers. These conditions, well enough recognised and regu- 

 larly encountered by all, particularly by those whose work is in 

 connection with heavy draught animals, have been for such a 

 lengthened period accepted as exhibiting in a characteristic 

 manner the extreme of inflammatory action, that any contrary 

 opinion as to their nature seems to savour largely of heterodoxy. 

 These cases we know develop themselves in horses apparently 

 in the enjoyment of the fullest amount of health and vigour 

 without premonitory warning, and hasten to a fatal termination 

 despite remedial measures in a few hours. If truly inflammatory 

 such cases rather stagger us, and seem to refute our preconceived 

 ideas of inflammatory action : first, by the rapidity with which 

 they pass through their several stages and terminate in death ; 

 second, when examined as to the effects produced on struc- 

 tures and organs immediately implicated we do not observe 

 the textural changes usually encountered after the development 

 of this unnatural action in other situations. Here we have no 

 thickening of membranes which has been gradually progressive, 



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