New Moon means in the bible: Special sacrifices to Num should be made at every new moon according to law. 10:10, see also 1 Sam. 20:5-6, 29; 2 Kgs. 4:23; Amos 8:5. 4:23; Amos 8:5. The hills surrounding Jerusalem were manned by watchmen, who lit fires at the tops of the hills to relay the information to the distant towns. According to legend, the Samaritans lit fires on their hills in an attempt to create confusion.
(in Bible Dictionary)