Exodus 38:8
basin <03595> [the laver.]
mirrors <04759> [looking glasses. or, brazen glasses.]
The word {maroth,} from {raah,} to see, denotes reflectors, or mirrors, of any kind. That these could not have been looking glasses, as in our translation, is sufficiently evident, not only from the glass not being then in use, but also from the impossibility of making the brazen laver of such materials. The first mirrors known among men, were the clear fountain and unruffled lake. The first artificial ones were made of polished brass, afterwards of steel, and when luxury increased, of silver; but at a very early period, they were made of a mixed metal, particularly of tin and copper, the best of which, as Pliny informs us, were formerly manufactured at Brundusium. When the Egyptians went to their temples, according to St. Cyril, they always carried their mirrors with them. The Israelitish women probably did the same; and Dr. Shaw says, that looking-glasses are still part of the dress of Moorish women, who carry them constantly hung at their breasts.
women ... served <06633> [assembling. Heb. assembling by troops.]
It is supposed that these women kept watch during the night. Among the ancients, women were generally employed as door-keepers. See 1 Sa 2:22.