188 ESSENTIALS OF VETERINARY LAW 
the city had exceeded its authority in framing the 
ordinance, so that the enactment is void, the offi- 
cer cannot plead as justification either the fact 
that he was complying with the terms of the ille- 
gal enactment, or that he was acting in good 
faith.1® It therefore becomes evident that the 
governmental veterinarian should not be content 
with mechanically following the statute, or the 
orders of his superior officer. He should learn at 
least the principles of law governing the position. 
102. Quarantine. An infectious disease is a 
nuisance, and as such it should be abated. The 
animals in which it exists are not of themselves 
nuisances, and they have commercial value in 
most cases. The disease cannot be summarily 
abated without also destroying the animals. For 
this reason we are accustomed to adopt certain 
restrictive measures. At one time the only method 
upon which dependence was placed was quaran- 
tine. The period of isolation may safely be mate- 
rially lessened by certain modern methods by 
which the disease germs, or their carriers, are 
destroyed, without injuring the stock. 
103. Quarantine Does Not Depend upon Statute. 
Where there is an enactment directing where and 
how a quarantine shall be established, that enact- 
ment must be observed; but where the law is 
silent, the police power of the community will 
support any reasonable measure taken for the 
19 PuBLC HEALTH, 361; Fisher 196; Cunningham v. Macon R. 
vy. MeGirr, 1 Gray, 1; Ely v. BR. Co., 109 U.S. 446; Poindex- 
, 
Thompson, 3 A. K. Marsh, 70; ter v. Greenhow, 114 U. S. 270; 
Osborn v. Bank, 9 Wheat. 738; Sumner v. Beeler, 50 Ind. 341; 
Norton v. Shelby Co., 118 U.S. Board v. McComb, 92 U. 8. 531. 
495; U. S. v. Lee, 106 U. S. 
