The board of supervisors of each county shall have the jurisdiction and power necessary and proper for the relief and support of the poor of its county, and it shall have control of the county home, and may employ a suitable person to take charge of the same. It shall see that the poor are properly treated; and it may provide nurses and physicians in such cases as it may deem proper, and purchase medicines, and payment therefor may be ordered out of the proper fund by warrant on the county treasurer.