The Cattle-P'uifjur. 263 



himself to the investigation, presented his secret to the Dutch 

 Government, who exposed it to the scrutiny of a Commission, 

 and finally gave it their authorization. It is now very commonly 

 practiced in the colonies ; but here not to such an extent as it 

 should be, considering the number of cattle that annually sink 

 of this disorder. Looking back we find that Dr. Layaed, in 

 1787, said, "But if the contagious distemper be in the neigh- 

 Ijourhood of a herd, or break out so as to endanger the stock, the 

 grazier or farmer may, by inoculating his cattle with proper ])re- 

 cautions, at least secure his stock, since he can house them before 

 they fall sick, prepare them, and have due care taken, knowing 

 the course of the distemper." He quotes the encouraging results 

 obtained by Camper, in Holland, who, out of 112 inoculated 

 beasts, saved 41 ; and those of KoOPMAN, Avho, out of 94, re- 

 covered 45. The Russian veterinarians having observed that the 

 oxen which had been cured of the rinderpest could mingle with 

 impunity with the infected herd, conceived the idea of com- 

 municating the complaint to sound cattle by means of inoculation, 

 and thereby to shield them froin the contagion. The first 

 experiments made in 1853, near Odessa, by Professor Jessen, 

 were very fatal. In 1854-5, the experiments repeated at the 

 Dorpat Establishment with better-selected virus, and at Kozan, 

 were more successful. They were led to conclude that it was 

 necessary to inoculate several heads of cattle, the one after the 

 other, without having recourse to any other virus than the first 

 inoculated, so that they may thereby obtain virus of the second, 

 third, fourth, fifth, and up to the tenth generation. The virus 

 thus attenuated in its toxical properties answered at length in 

 every experiment, and oxen thus inoculated could mingle with 

 impunity with diseased cattle. At the Veterinary College of 

 Charkow they inoculated 1059 animals with virus of the third 

 generation, 60 animals only sinking under the operation. In 

 1854 a large number of the cattle of the Steppes. were inocu- 

 lated and not one lost, and all were found to be fortified 

 against subsequent attacks. In 1857 the Grand Duchess Helena 

 founded an institution for inoculation on her property at Kar- 

 lowka, in Poltiiva, with such success that only 3 per cent, of 

 the inoculated animals died. Dr. Playfair reminds us that these 

 favourable results are obtained with Steppe cattle ; and adds, 

 " before mitigation of the virus appears in the case of other races 

 of cattle it must pass through from thirteen to fifteen generations." 

 Professor Jessen is of opinion that no cattle should be imported 

 from the Steppes without this safeguard. M. EaupaCH, another 

 experienced inoculist, reporting, in 1864, from Karlowka, says, 

 after stating that in 75 experiments 40 per cent, of recoveries 

 was obtained, " I do not, hov»ever, recommend inoculation as a 



