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Colony, in a letter published in the Sydney and Melbourne papers of 

 December, 1861; and the first to make the attempt was Mr. Thomas Mitchell, 

 Little River, Victoria. Shortly afterwards (about the middle of January, 1862) 

 the Messrs. M'Laurin, of Yarra Yarra, New South Wales, and other owners 

 in their neighbourhood, also tried inoculation, with decided success. The 

 reports of these experiments, which were published from time to time by the 

 Government of New South Wales, speedily induced other stock-owners in all 

 the Colonies to try the operation ; and inoculation, as a preventive for pleuro- 

 pneumonia, is now generally practised throughout Australia, and, as the 

 stock-owners report, with decided success. 



Thei'e have certainly been frequent instances of the failure of inoculation ; 

 but these, the stock-owners state, could always be traced to one or other of 

 the following causes : — 



1. To the cattle leing badly diseased when operated upon. — In most cases 

 the owner did not inoculate until he was thoroughly alarmed, and he did not 

 become so until he lost perhaps 15 or 20 per cent, of his cattle by the disease. 

 The consequence was, that when he did inoculate, three-fonrths at least of his 

 herd were diseased, although they, perhaps, did not appear to be so ; and the 

 operation would require to be a cure, as well as a preventive, to be thoroughly, 

 or even moderately efScacious under such circumstances. 



2. To the vse of improper i^h'us. — The directions fn-st received for selecting 

 the right sort of lung and virus were very vague and meagre, and a great deal 

 of virus which was worse than useless, in fact actually deleterious, was used 

 by those who were most anxious to perform the operation correctly. It was 

 at first no imcomraon thing to see virus taken from the lung of an animal 

 which had died of the disease, and which was, of course, quite unfit. Through 

 a sadly mistaken economy, virus was frequently also taken from animals in 

 the last stage of the disease, and likewise from portions of the lung in a far 

 too advanced stage. Virus, again, which has become stale and putrid through 

 keeping was frequently used, out of ignorance or carelessness. Not only was 

 a great deal of virus which was thoroughly unfit used in those ways by 

 owners and others who were most anxious to perform the operation correctly, 

 but many pretended professional inoculators, who knew little or nothing as to 

 how the operation ought to be performed, and who did not care what sort of' 

 stuff they iised, so long as they made, as they often did, from £5 to £10 a 

 day, went about from station to station inoculating, and it was quite impos- 

 sible that in their case the operation could be attended with success. 



3. To a wronff mode of operating. — The first instructions on this head also 

 were very defective, or rather erroneous. They directed that a piece of the 

 diseased lung should be inserted under the skin of the tail. To perform the 

 operation in this way without injuring the animal requires the greatest care 

 and nicety of operation, and these were seldom or never bestowed upon it. 

 The consequence was that the tail was lacerated, frequently to the bone, and 

 dangerous swellings and sloughing ensued. In other cases, again, a rag and 

 tie were used to keep the piece of lung attached to the tail, and in this way 

 inflammation and sloughing in the tail or rump were almost certain to be 

 induced. Even after better information had been obtained, and considerable 

 experience acquired in taking the virus and inoculating, the operation was 

 frequently badly performed through carelessness and haste. 



4. To the gre€Ll heat of the weather when the cattle were inoculated . — At 

 certain seasons of the year the weather in Australia is by far too hot for an 

 operation of this description when performed on quiet cattle ; and it can 

 easily be seen how very much worse it would be, and how many more cases 

 there would be of mal-inoculation in such weather, with comparatively wild 

 " bush" cattle, which are always heated and excited when driven into the yard, 

 and almost maddened by the operation in the inoculating pen. 



