Over Thanksgiving week the wife and I took a 7 night cruise on Delta Queen Steamboat Company's magnificient Mississippi Queen. The cruise was originally booked to go from New Orleans to Memphis, but Bitch Katrina intervened. Since the dock facilities at N.O. were somewhat compromised by Katrina, the cruise was rescheduled to go from Nashville, TN to Memphis, TN. That distance, across TN doesn't seem so far, but it is a long way to go by water.
Routing was Cumberland to the Ohio and then North on the Ohio to Cave-in-Rock, IL; turnaround at Cave-in-Rock and back down the Ohio to the Mississippi and thence to Memphis. We had great shore trips to some Civil War battlegrounds and stopovers in several of the river towns, including Paducah, KY. In Paducah, I found an 1895 book on electric motors, a very welcome addition to my collection.
Naturally, I got a tour of the engine room on the Mississippi Queen. This was against security regulations and had to be specially arranged - otherwise, there would have been a case of passenger mutiny on the high river! Imagine me standing up close and personal along side the monsterous steam engines. (two of them on either side of the paddlewheel with cranks at 90 degrees). The engines had a 10 foot stroke. Each engine was steeple compounded with high pressure and low pressure cylinders of 16 in. and 32 in., respectively, on a common piston rod. I couldn't get a good look at all of the valve gear.
The operator didn't know the exact description of the valve gear. It looked, to me, to be a form of modified Hackworth, driven from the connecting rod, ala single eccentrics, as in regular Hackworth. There was an arm that toggled back and forth operated by the con rod (single eccentric ?) and that arm in turn imparted motion to cams which drove the valve rods. Cut-off was controlled by linkages on the valve rods. As steamboats go, it is a youngster, being been built in 1976. Does anyone have a more accurate description of the type of valve gear on the Mississippi Queen?
Bob Swinney