<html> <body> Hi, Patrick, At 05:39 PM 6/19/2006, you wrote: <blockquote type=cite class=cite cite="">  <dl> <dd>Horace: It does appear that whatever was screwed onto the lever was attached directly above at the bottom of the keybed, where there are two empty screw holes. It seems that there must have been something there to keep the sostenuto from engaging without use of the pedal, and also to keep the assembly aligned in place, as the vertical bar is only held in by the pressure on the relatively weak spring. </blockquote> </dl> Yes. <blockquote type=cite class=cite cite=""> <dl> <dd>The  3 screw holes on the bottom of the right end of the horizontal lever are countersund,which would seem to mean that the screws there came up from below and went into some kind of wooden piece above. The interesting thing is that there are 3 holes in the lever, but only 2 holes above in the bottom of the keybed.  Maybe there was a hinged and spring-loaded two-piece bar that rode on the graphited end of the horizontal lever that both kept the assembly in place and returned the horizontal bar to its place when the pedal was released?</blockquote> </dl> That's what I was thinking.  If the pedal itself is not set up with a notch to hold things in place when applied (it's not clear in the picture if that is the case or not), then something along the lines you are suggesting would have to be in place to allow the sostenuto to be applied and released with two motions of the pedal.  I was thinking some kind of spring-loaded assembly which provided such a locking mechanism at the end of the lever, stabilized (somehow) by another vertical, perhaps also floating, strut. <blockquote type=cite class=cite cite=""> <dl> <dd> And also an elbow-shaped piece going over to the pedal? </blockquote> </dl> If there are no other signs of mounting anything to the horizontal lever, possibly so.  That, too, would fit into a mechanism which allowed for an on/off operation of the sostenuto. <blockquote type=cite class=cite cite=""> <dl> <dd>This is starting to sound as strange as a Chickering !</blockquote> </dl> Some really marvelous designs on instruments from this period...which leads me to wonder if there are any patent notifications on the instrument that might have to do with pedal trapwork.  If you can date the instrument with any accuracy, you might be able to see if there are any pedal/etc related patents issued to Baldwin around that time.  If there are, you can get copies from the Patent Office fairly reasonably.  Because of the fire of 1876 at the Patent Office, anything before that can get problematic...but the plate on this instrument looks like a later design, so, who knows? As to sounding as strange as a Chickering...define "strange".... Cheers! Horace </body> </html>