440 KEPOET OF THE BUKEATJ OF ANIMAL INDUSTRY. 



only possible exception. Contact through pasturage was denied to 

 the Norris cattle. Contact through drinking water was probably 

 denied to the bell team. Those native cattle which were known to 

 have most communication with the infected cattle are those that died. 



The stage of incubation in the outbreak among the native cattle 

 occupied about the same length of time as in the infecting herd. 

 With some of the animals the time seems to have been shorter among 

 the natives, indicating a greater virulence of the disease, but this 

 may simply have been due to the fact that the natives were milch 

 cows and less able to resist the contagion. Mr. Norris' first cow that 

 died offers the shortest time that we are entirely certain of. The 

 eight days' incubation of Mr. Baker's cow is the shortest, but showing 

 an illness on the first night that it is driven home vitiates the accu- 

 racy of the statement. I think, however, that the cow died of South- 

 ern cattle fever, and this time is the shortest of which there is record. 

 Excepting the last three of Mr. ISTorris' cattle, which died in nineteen, 

 twenty -four, and thirty-one days, respectively, all died within two 

 weeks after the first possible exposure. The two exceptions may 

 have died within two weeks after exposure, as there is no certainty 

 when they were first infected. It must be remembered that the 

 stages of incubation given in Table IY not only include the time of 

 stage of infection, but also the time of the stage of fever. If we allow 

 one day only for the stage of infection and two days for the stage of 

 fever there are left eight, ten, eleven, sixteen, twenty-three, and 

 thirty days, excluding Mr. Baker's cow, which had five or six days. 

 The three cows belonging to Mr. Norris, which died in nineteen, 

 twenty-four, and thirty-one days after infection, offer to us the sug- 

 gestion that they may have contracted the disease from each other 

 in turn, as Mr. JSTorris himself thought. The stage of fever in all 

 these oattle occupied about two days each. 



In conclusion, I would point out that the facilities for obtaining 

 the facts in the above outbreak, as well as its peculiar characters, 

 make the history of this outbreak an important one in the clinical 

 history of the disease. In comparing this outbreak with others it 

 will be found that there are but few which record such a short period 

 of incubation, especially among the natives, which have been more 

 virulent, and show a clearer record in regard to the infection and 

 disease among natives. 



In regard to the outbreak of disease among cattle near West- 

 minster, Carroll County, Md., I have the honor to report as follows: 



Mr. Harry Cover, of Westminster, bought 105 head of cattle in Chicago on the 

 10th of August, 1888. The herd was composed of numerous small lots. These cat- 

 tle were loaded 011 the 18th of August and shipped to Taneytown, Md., where they 

 arrived on the 17th. They were unloaded and fed at East Liberty, Pa., on the 15th. 

 There were but few marks designating the original pastures of these cattle. The 

 ear tags of a f ew showed that they came from Missouri. 



On the 18th of August the cattle were distributed to these farmers: Samuel Cover, 

 53 head: B.F.Shryver, 30; Edward Matthias, 5; Allie Shafer, 6; Fred Bachman, 1; 

 Mr. Myers, 10. 



Of Mr. Samuel Cover's herd, 8 head died and 4 others were taken ill. One died on 

 the 25th of August: 3 on the 26th, 2 on the 29th, 1 on the 31st of August, and 1 on 

 the 1st of September. Mr. B. F. Shryver lost 1 on the 25th of August. There was 

 1 other animal which either strayed away or died. Mr. Edward Matthias lost 1 on 

 the 26th of August. This makes a total of 10 head which died. 



