Ha !
I roped in yet another engineer !!!
No. the collapsible cart (with the rectangular carrying area) would be to move a c. 24 lb. tuba (plus its 8 lb bag) from an automobile into a rehearsal or performance venue (which - at least, to me - seems more sensible than selling off something very nice - like a Miraphone model 186, and buying something to replace it that - weighing a bit less - is "pretty good" - such as an Old model O-99, in order to carry around a few less lbs. of tuba).
I particularly appreciate the York picture (above), because the stated weight (of the B-flat) supplies very strong evidence that (though everything is shorter, with the tuba on the right) that the tuba ON the right was not always a "featherweight" tuba (as the current trend seems to be to produce "copies" of it fabricated of Cerveny-esque .5mm sheet brass, rather than realizing that it was formerly a satin-silver finish tuba, and there are plenty of old pictures to be found, demonstrating this), and that - decades ago - it's previous owner (sadly) allowed someone to absolutely "buff the $h!t out of it" - (again: sadly) buffing away "lbs. of tuba".
I would imagine that -
originally -the tuba on the right (rather than - and I've held/played it - it's "might blow away in the breeze" weight) might have originally weighed 31.5 (??) lbs. vs. your longer-everything B-flat version, which you report weighing in at 35 lbs.
I also suspect that part of the reason that the Donatelli guy may not have been interested in screwing around with that thing (selling it off to a student after not too much time passed) is because
(and no, he was
NOT a "fat guy", as been wrong pur
PORTed)
- It weighed over 30 lbs.
- The subsequent Conn probably only weighed 22 or so lbs. (an ACTUAL significant difference of c. 10 lbs.)
- The subsequent Conn was easier to play in tune.
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With it's very WHITE appearance - in this picture (just as with current freshly bead-blasted and silver plated instruments), I strongly suspect that this picture was posed with the instrument when it was VERY new.