DISEASES OF SWINE AND OTHER ANIMALS. 67 



cated three years ago by Professor Axe, who successfully inoculated a 

 pig V, ith vii'us that had remained dried upon i^ory points for twenty- 

 six days. It seemed important to test this by further experiment, as 

 n])oii this question depends the weighty one of arresting or putting an 

 end to the plague by the extinction of its poison. 



Three pigs were inoculated with virulent products that had been 

 di'ied on quills for one day, one Asith virus dried on the <iuill for four 

 DAYS, one for five days, and one for six days. The quills had been 

 sent from Xew Jersey iind Xorth Carolina, wrapped in a sim])lc paper 

 coveriug, and therefore not in any way specially protected against 

 the action of the air. Of the six inoculations, four took effect, and in 

 the two exceptional cases the quills had been treated with disinfectants 

 before inoculation, so that the failure was to be expected. 



Viridcncc of the dried intestine. — In the case of the quills, the virus 

 was dried quickly on account of the tenuity of the layer, and no time 

 was allowed for decomposition. With the diseased intestine the drying 

 in the free air and sun was necessarily slower, and more time was 

 allowed for septic changes. Three pigs were inoculated with diseased 

 intestine which had been diied for three and fouk days respectively. 

 In one case the diseased product was from j^orth Carolina. In all three 

 cases the inoculation proved successfid. The morbid product, therefore, 

 even in comparatively thick layers, may dry spontaneously, so as to be 

 the means of transmitting tlie disease to the most distant States. 



Yirnlence of the moist morhid product if secluded from the air. — A pig- 

 was inoculated with a x^ortiou of diseased intestine sent from Illinois in 

 a closely corked bottle. The inoculating material had been three days 

 fi'om the pig and smelt slightlj' putrid. The disease developed on the 

 sixth day. 



A second pig was inoculated with blood from a diseased pig that had 

 been kept for eleven days at 100*^ Fahrenheit in an isolation apparatus, 

 the outlets of which were plugged with cotton wool. Illness supervened 

 in twenty-foiu- houi's. 



The exclusion of air, or more probably the prevention or retardation 

 of putrefaction, therefore, probably favors the longer preservation of 

 the poison. 



Frobahle non-virulence of morhid products that have undergone putrefac- 

 tion. — Two pigs were inoculated in one day with the elements of an ulcer 

 from a portion of intestine sent from ISTew Jersey in a box. Tlie pioduct 

 was TWO DAYS from the pig and distinctly putrid. Neither seenied to 

 suffer at any time. 



A tliird })ig was jilaced in a pen with a portion of the same diseased 

 intestine, and some manure s«nt v,ith it. The intestine disappeared 

 after the second day, and was probably eaten, but the pig showed no 

 evil effects. 



It should be stated that each of these pigs had been formerly inocu- 

 lated, and two appeared to pass tlirough a mild form of the disease, 

 while the third had showed an elevated temperature on thiee alternate 

 days only, it may therefore be questioned whether they had not at- 

 tained to a certain degree of insus(*ej)tibilit;\ wliicli insured the negative 

 results. In other cases, however, 1 liave found a second inoculation to 

 take though the first had been successful, aud Dr. Osier records cases 

 of the same kind. The resvdts obtained in the three above-mentioned 

 jjigs would th'maiul furtlier investigation in tliis direction, as they sug- 

 gest a ])ro])able explanation of any varying virulence of the disease in 

 wet and dry seasons, in sheds and in tlie lields. 



If we can accept Dr. Klein's tlieory of the baccillar origin of the diseasei, 



