Ezekiel 1:15

One wheel upon the earth - It seems at first view there were four wheels, one for each of the living creatures; that is, the creatures were compound, so were the wheels, for there was "a wheel in the middle of a wheel." And it is generally supposed that these wheels cut each other at right angles up and down: and this is the manner in which they are generally represented; but most probably the wheel within means merely the nave in which the spokes are inserted, in reference to the ring, rim, or periphery, where these spokes terminate from the center or nave. I do think this is what is meant by the wheel within a wheel; and I am the more inclined to this opinion, by some fine Chinese drawings now before me, where their deities are represented as walking upon wheels, the wheels themselves encompassed with fire. The wheel is simply by itself having a projecting axis; so of these it is said, "their appearance and their work was, as it were, a wheel within a wheel." There were either two peripheries or rims with their spokes, or the nave answered for the wheel within. I have examined models of what are called Ezekiel's wheels, which are designed to move equally in all directions: but I plainly saw that this was impossible; nor can any kind of complex wheel move in this way.

Translate it: "one wheel upon the earth by" each of "the liviing creatures" on his four sides (i. e. on the four sides of each of the living creatures). There was a wheel to "each" of the living creatures: it was set "by," i. e. immediately "beneath" the feet of the living creature, and was constructed for direct motion in any of the four lines in which the creatures themselves moved. Their "work" or make, i. e. their construction, was "a wheel in the middle of a wheel;" the wheel was composed of two circumferences set at right angles to each other, like the equator and meridian upon a globe. A wheel so placed and constructed did its part alike on each side of the living creature beneath which it stood. The "ten bases" of the temple 1 Kings 7:27-36 were constructed with lions, oxen, and cherubim, between the ledges and wheels at the four corners attached beneath so as to move like the wheels of a chariot.

1:15 Living creatures - By each of the living creatures stood one wheel, so that they were four in number, according to the number of living creatures. Four faces - By this it appears, each wheel had its four faces. While he was contemplating the glory of the former vision, this other was presented to him: wherein the dispensations of providence are compared to the wheels of a machine, which all contribute to the regular motion of it. Providence orders, changes: sometimes one spoke of the wheel is uppermost, sometimes another. But the motion of the wheel on its own axle - tree, is still regular and steady. And the wheel is said to be by the living creatures, who attend to direct its motion. For all inferior creatures are, and move, and act, as the Creator, by the ministration of angels directs and influences them: visible effects are managed and governed by invisible causes.