Adam Clarke on Job 37:18

Hast thou with him spread out the sky - Wert thou with him when he made the expanse; fitted the weight to the winds; proportioned the aqueous to the terrene surface of the globe; the solar attraction to the quantum of vapours necessary; to be stored up in the clouds, in order to be occasionally deposited in fertilizing showers upon the earth? and then dost thou know how gravity and elasticity should be such essential properties of atmospheric air, that without them and their due proportions, we should neither have animal nor vegetable life?

Strong - as a molten looking-glass? - Like a molten mirror. The whole concave of heaven, in a clear day or brilliant night, being like a mass of polished metal, reflecting or transmitting innumerable images.