A reasonable vacation without thereby subjecting the city to additional expense might well have been regarded by the city council as calculated to promote the health and efficiency of the police force, and, if so, we think that it was within the power of the city council to adopt the order which it did. It would come fairly within the authority conferred on cities and towns to make such reasonable provisions as they should deem conducive to their welfare “ for directing and managing the prudential affairs, preserving the peace and good order, and maintaining the internal police thereof.” Pub. Sts. c. 27, § 15; c. 28, § 2. It would also come within the power conferred on the mayor and aldermen of Haverhill to make such regulations for the government of the police department not inconsistent with law as they deem proper. St. 1894, c. 480. Malcolm v. Boston, 173 Mass. 312. Bill dismissed.