This is an engraving, black and white with shades of grey made from parallel lines of varying distance and thickness.
The engraving shows a fixed steam engine presumably used for powering a printing press.
The machine consists of a large square hollow box mounted firmly on a plinth with a round tube coming up out of it. The tube contains a cylinder, the main part of any steam engine, and, coming out of the top of the cylinder, a rod rises vertically upward with a horizontal bar fixed to the top of it. This rod will move up as the cylinder-head inside the cylinder is forced up by the pressure of the steam, so although the picture does not show the actual cylinder head hidden inside the cylinder, we can envision the rod moving up and down. Connected to each end of that horizontal bar on top of the rod is a long rod that goes all the way back down into the box under the cylinder, through a long slot in the box. Because the box is hollow we can see through the sides that the rods connect to a large heavy crankshaft inside the box. The crankshaft in turn connects to a large wheel mounted behind the box, and that wheel has a belt going round it that presumably would connect to the printing press in some way.
Note that since the crankshaft is in the box near the bottom of the machine, the wheel must go below the box as much as it goes above it, so the machine mightr be mounted next to a pit.
There are also steam-pipes and a governer, which is a device with two heavy balls fastened to rods that dangle from a vertical spinning pole; as the pole spins faster the force makes the balls want to push outwards more, lifting the rods to which the balls are fastened; another pair of rods goes downwards from the base of each ball to the poll, and as the balls lift these smaller rods pull up until they reach a protrusion in the central poll, at which point the supply of steam is cut off or reduced. In this way the governer limits the speed of the engine.
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