Re: weight of a bird in a cage

[Ludwik Kowalski <KowalskiL@MAIL.MONTCLAIR.EDU>]

Are you saying that the net weight of the "box with the
fly inside" remained nearly constant (+ or - the weight
of 0.1 mg) no matter what the fly was doing?

Jim Ealy wrote:

> Listmembers;
>
> My nature always says go to the lab when I hear "opinions" (I know that
> places me several rungs down THE ladder)
>
> My high school students several years ago made a box from dry-cleaner's
> plastic wrap and balsa - total was less than 20 grams about 50 cm by 50
> cm. A closed system sealed with tape, after fly was inserted - positive
> pressure.  We waited until spring to capture one of those large flies
> (commonly called - casement flies) that emerge in rooms.  They placed the
> fly in the "box" and placed it on a top-loading balance: 0.1 mg.  There is
> no question about what happens (flying,landing, starting off from bottom
> or side or top (or repeating after punching holes in plastic for air to
> move in or out as in an open system)). "It" only becomes difficult when we
> as teachers try to make "it" more than "it" is.
> ................butterflies "work" well also.
> Jim Ealy
> Education by Demonstration