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>Cave divers of the world,
>
>I'm interested in learning if you breathe your long hose or your
>short, as a primary.  This only pertains to dives with back mounted
>tanks, utilizing a manifold.  When, or if you choose to respond,
>please take the time to include why you've taken the decision you have.
>
>I dive (inside wrecks) with my long hose as my primary and my shorter hose
>around my neck on surgical tubing becasue I tell my buddy just to take the
>rig from my mouth if they need air and to pull out the hose from the coil
>on the side of my BC.  This is what a diver suffering from panic would do
>anyway and I don't find the extra hose to present a significant restriction
>even as deep as 250fsw.

Hi, firstly let me introduce myself, I am Dr Ali Lawrie (AKA Wilkins) and dive
both in open water and also in caves. My training in caves in Britain has
led me to dive at all times with two independant breathing systems (usually
of the same capacity). In this country you will find that most cave divers
use regulator hoses of the same length thus removing the problem addressed by
the first comment above. 

On the use of manifolds, I can see the point of having two different lengths
of hose-especially useful in the case of having to buddy breathe, as in the
second comment. The problem that I have with these systems is this:
	The idea - as I understand it - is that one dives with one regulator 
and in the event of a failure this regulator can be isolated by the mainifold
to enable the second to be used safely to exit the water.
	This all looks, and sounds rather wonderful, but if your first reg.
is free-flowing (as is most likely) and it is essential to turn it off to
change to the back-up, then how on earth do you reach behind you to turn the
tap?! I don't think that I am the exception in saying that I cannot even touch
my taps when diving back-mounted let alone turn them! Remember that you cannot
rely on your buddy being behind you at the right time!
	When diving with two cylinders then there is always a fully functioning
reserve with which you can get yourself out of trouble if your buddy is miles
away (e.g. taking photos). For cave diving self-sufficiency goes one step
further: by side-mounting, cylinder taps can easily be accessed thus making
them easy to turn off if necessary.

I would be interested in any comments that any of you out there have on the 
use of manifolds vs independant systems (twin sets).

As I am a new subscriber you may be interested to know that I have been diving
since 1988, I took up cave diving as I am also a caver (essential for
most British sumps). If anyone requires information about cave diving in
Britain then please contact me direct: I am the National secretary of the
Cave Diving Group, E-Mail:  aml@li*.ac*.uk*.

Cheers!
Ali

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