Box 67, Austinburg, Ohio
I am sending to the Album a picture of a Port Huron double cylinder tandem compound engine. So far as I can learn only three companies built engines of this type. We know Garr Scott built them in their Big Forty. It appears Minneapolis also built some, but I have owned or seen Minneapolis catalogs covering most of the years back to the turn of the century but have never seen one showing a tandem compound double.
Apparently many engines of various kinds were built of which pictures are scarce or non-existent. Every so often I see references to Advance cross compound engines. I have seen many Advance catalogs but never a photo of a cross compound. I know Advance built a rear mounted single late in the career of the company, but I would like to see a photo of an Advance double, which it would have to be if it were cross compound. I once came across a mention of a 50 x 150 Nichols & Shepard. Could this be an error or did Nichols & Shepard actually build an engine of this size?
I have an engineers' handbook published back in the nineties that treats of a Port Huron engine with poppet valves. The illustrations are fuzzy and the description is meager but the idea I get is that there are two poppet valves moving back and forth in lines perpendicular to the line of travel of the piston. It does not explain how the valves are actuated. I have asked old engine men, some of them Port Huron men, about this engine and they claim never to have heard of it. Probably only a few of them were ever made.
In Floyd Clymer's book of steam traction engines there is a picture that puzzles me very much. On page 95 in the lower right corner there is a picture of a double cylinder Minneapolis engine. This shows the differential and idler gear on the left side. The clutch is on the flywheel on the right side. How is the power transmitted to the idler gear? I have seen several Minneapolis doubles, but they all had the gear train completely on the flywheel side as shown by the picture in the upper left hand corner of the facing page.
Speaking of flywheels, or band wheels, as some prefer to call them, how many readers know of one fracturing in heavy gear work? I know of one, a Minneapolis double, pulling twelve plows in prairie sod. It would seem the pressure of the clutch was more than the wheel could take and it broke into three segments. Two pieces landed forward of the engine and the third piece sailed back over the engineer's head. It was a bit of grim humor around the neighborhood to say 'the engineer kept his head.'