sealing the snake's gas fitting

["Chris Kent Kantarjiev" <cak@parc.xerox.com>]

I think that what you need is called a Dowty seal. It's a crush washer
bonded to an O ring, and is the standard sealing washer for BSP
fittings. When you get things apart, measure the size and call Dave
Bean; they can sell you the right thing.

When you assemble, coat the threads with Permatex green (#2, the
non-hardening one) for good luck and extra measure.