should be careful with long held dreams. They have a way of becoming
reality. Since my early teens I had dreamed of having my own boat and
exploring remote reefs and islands. In late 1967, at age 28, I was at last
able to place an order for my dream. It was to be a small long range well
equipped twin diesel steel research vessel. A beam of 28 feet in a
64 foot length provided plenty of room, a large fuel and water capacity
and exceptional stability in a compact shallow draft vessel I
could operate with minimal crew or even alone when necessary.
El Torito was named
after the Spanish name for the cowfish (Lactophrys quadricornis).
Literally it means "little bull". Both the fish and the bull references
seemed apt. For the next 20 years El Torito was to be my home and
take me from the Caribbean to widespread explorations through the Western
While El Torito was
under construction development of the Electrolung came about through a chance meeting of John Kanwisher and I aboard Ed Link's diving research vessel
Sea Diver in the Bahamas
in early 1968. Ed was trying out his new diver lock-out submarine Deep
Diver and had invited along several researchers with relevant interests. I
was there to do some deep biological collecting and John was there to do
heart rate/respiration measurements on divers using some new acoustical
telemetry equipment he had developed.
Lock-out dives from Deep Diver were done using hose fed open circuit Kirby Morgan
helmets. Gas for this purpose and to pressurize the lock-out chamber was
supplied from a large high pressure sphere carried by the sub. The large
amount of gas required for a single dive severely limited the number of
dives which could be made and involved substantial cost and logistic
considerations. The need for more efficient utilization of gas was clearly
It turned out that John and I had both been considering the feasibility of a
mixed gas closed circuit rebreather using electronic sensors to control PPO2. We both knew in
general terms what was needed but John wasn't a diver or a machinist and I
didn't know that much about electronics. However, I had been diving for 15
years and had built a wide range of underwater equipment and John, in
addition to being a physiologist, had invented the first polariographic
oxygen sensor and held a dual appointment at Woods Hole Oceanographic
Institute and Massachusetts Institute of Technology where he lectured on electronic instrument design.
When we returned to our homes John started putting together the sensors and
control circuit and I started designing the hardware and finding or machining
the components. Six weeks later we both had our respective parts
together. John sent me a bread board controller circuit and sensors. I installed them and it
and a few test dives showed that it indeed worked. The overall concept and design
appeared good but
there were of course, numerous details to clean up. The electronics for
example were wire connected on a breadboard and the solenoid valve I had
hand made using a solenoid scavenged from a battery operated cuckoo clock.
Although the prototype was put together quite quickly it was far from a
"first thing which comes to mind" effort. Quite a few years experience and
thought had led up to it so when actual construction began we both
knew pretty clearly what was needed and how to do it. Over the next few months we quickly followed
with a cleaned up version using printed circuit boards, a proper miniature
pneumatic control solenoid valve and sundry improvements to various details of the
A couple of years later,
after we had sold the commercial rights to the Electrolung to Beckman
Instruments, I had the opportunity of working with a team of high tech
on improving the same device. The outcome was some further tidying up of details
but no fundamental changes. The biggest problem was to prevent the
creation of problems which didn't previously exist but could be introduced
through changes made by specialists who were unaware of consequences outside
of the narrow area of their expertise. The experience gave me a
appreciation of both the strength and the limitations of specialist expertise
as well as the importance of systems analysis in coordinating and integrating specialist
John Kanwisher was also on one
of the advisory panels to NASA in connection with the Apollo program. Although
he recommended using a mixed gas atmosphere in the Apollo capsule he was
over-ridden by engineers who felt that monitoring the PPO2 was too difficult.
John knew better as he had been doing it for several years in conjunction with
his work on respiration but the engineers prevailed. The result was a fire which
killed three astronauts after which they switched to a mixed gas atmosphere.
In late 1968 the first
operational version of the Electrolung was ready to go and so was El Torito.
In November of that year I set out for Cozumel aboard El Torito with
several new Electrolungs. Over the next few weeks I conducted a series of
dives culminating in a descent to 400 feet where I photographed and collected a
new species of gorgonian. During the next two years I dived the Electrolung
exploring the deep outer dropoffs of reefs from Cozumel to Belize and in various
location in the Bahamas. This work involved the discovery of several more new
species of fishes and invertebrates.
A story in the
August 1970 issue of Skin Diver Magazine told the story of the development of the
Electrolung and the September issue followed with a story by Paul Tzimoulis on
making a 300 ' Electrolung dive with us on "The Wall" off Fresh Creek,
Andros Island in the Bahamas. My story, "Probing the Deep Reef's Hidden
Realm", appeared in National Geographic Magazine in December
Although development of the Electrolung was exciting, in
itself it was just an interesting incident in a bigger, more interesting
and more significant picture. Like most historical events, I suppose, what was
happening didn't appear to the participants at the time so remarkable as it
later does in the broader perspective of hindsight. The larger view what is taking place
at any time tends to be somewhat obscured by the
ordinary events of living. Except for rare instances whatever we are doing,
however interesting and exciting it may be, tends to still feel like life,
not like history in the making.
In retrospect however, I have come to realize that from the mid 1950s through
the mid 70's something remarkable was taking place in diving.
During that period it grew from the obsession of a small group of
generally impecunious young people mostly in FL, CA, France, and Italy to a
global industry catering to relatively well-to-do hobbyists. Remote tropical islands
all over the world began to sprout airports and dive operations and diving
became strongly oriented to travel to exotic locations. Though all this
was in itself remarkable something truly unique was at the heart of
what was happening.
For the first time in history humans could freely enter, explore and
personally experience the oldest, richest, most beautiful and exotic
communities in nature, tropical coral reefs. Coral reefs are truly
special places. Nowhere else can one experience such an abundance and
diversity of life. Nowhere else is it so colorful, exotic and so easily
experienced at close range.
Diving on a reef is like a trip in a time machine to a time before humans
existed and nature ruled in primeval pristine abundance. Fossils of many
reef creatures from as much as 60 million years ago are essentially the same
as those on reefs now. In fact some Pacific reefs have continuously existed as reefs for
that period of time. Considering that our own evolution from ape to today's
humans has all taken place in about 3 million years this is truly a vast span of
time. Sixty million years ago or even 5 million years ago on land you
would find a world of creatures very different from today's animals but on reefs
you would feel right at home surrounded by corals, fishes, and other creatures
very similar to or even indistinguishable from those we see today.
For a biologist, being among the first to dive on reefs was an extraordinary
experience. In a way it was a bit like landing on another planet. On
nearly every dive you were going where no human had ever been before. The
discovery of phenomena of life and strange and beautiful creatures whose
existence we never even suspected was an everyday occurrence. At the time
this kind of experience was so commonplace, tropic seas so vast and remote,
and so few people were doing it, that it began to seem as if this was just
the way things were and this kind of experience would continue
Already however, this era has become history. Although there are vast
amounts still to be learned about the details and inner workings of
reefs, undiscovered species are getting harder and harder to find and
remote locations are becoming less and less remote. The experience of being
among the first to explore the richest realm of nature has come and gone,
not to be repeated.
On reefs, one niche still remains. Actually it is a really big one. The
zone below 200 feet, down to the deepest limits of what you might call part
of the reef community at about 600 feet, is still largely unexplored.
Although it is not so rich in life as the shallower regions it is still quite
and is an area about which we know very little.
As far as I am aware the only person on the planet regularly exploring this
zone is Rich Pyle from Hawaii. As well as making more deep free dives
than anyone ever has before he is coming back with knowledge and specimens
from every dive. What he is doing is a permanent contribution to knowledge
which will stand long after any of today's diving records are broken and
forgotten. I have never met him personally and am commenting only out of
recognition of something exceptional.
Over the past 25 or thirty years advances in diving technology have been
almost entirely small and incremental. The only real exception I can think
of is the development of dive computers. It appears we are up against the
realities of human physiology. With every increase in depth and bottom
time the cost, complexity, effort, and risk increases exponentially while
the return of useful achievement remains more or less linearly related to
The future would seem to lie in other directions, especially robotics. Here
advances have been impressive and future development promises to become even
more so. Already we are at a point where more and more functions previously
requiring a diver can be effectively carried out by remote operated vehicles, ROVs . It is not hard
to foresee that in a few years most of what we do at great effort and risk
by diving can and will be done by an operator at a console. Currently increasing
amounts of offshore oil and gas drilling is taking place in depths beyond the
reach of divers with all operations at the wellhead being carried out by ROVs.
Even within diveable depths ROVs are taking over more and more of the tasks
previously done by divers.
If as a diver you find this kind of scenario uncomfortable, don't let it worry you.
Long term prediction, no matter how well reasoned and seemingly inescapable,
has a way of almost always being wrong. So much so that I have often
wondered if beneath the facade of Newtonian certainty of our universe ,
somewhere in the iffy probabilistic realm of quantum mechanics, there is not
something which dictates that the very act of prediction sets in motion
forces which generate a different outcome. So if you don't agree with my
prediction, the good news is that I may well have voided it by predicting
Fortunately, the real outcome is usually even more interesting than any of
Many dedicated underwater photographers are currently wondering about the pros
and cons of rebreathers. The following from a recent post by myself to the Rebreather Discussion List may provide some thoughts worth
debate over the role of design, error, and training in rebreather fatalities
seems to involve more than a hint of denial. That is, it won't happen to me
because I don't use that unit, or wouldn't make such a stupid mistake, or have
been properly trained. It also tends to obscure one overwhelmingly important
fact. All rebreathers are inherently dangerous. The overall fatality rate with
RBs is about an order of magnitude greater than with open circuit and with the
latter the majority are beginners while most of those with RBs are "experienced"
Regardless of design, RBs incorporate a variety of means by which through error,
inattention or failure they can kill you. Where the cause of accidents are
known the overwhelming majority are attributable to operator error of a type
that neither design nor training are likely to prevent. Rebreather use demands
good mechanical and instrument sense, meticulousness, multitasking ability, and
risk assessment judgment.
While design and training are important they cannot make up for inaptitude,
carelessness, distractibility, or poor judgment. Many very capable and
safe open circuit divers are simply unsuited for RB diving. Until we recognize
and learn to assess the requisite human parameters of RB diving the harsh rules
of natural selection will continue to be reflected in the mortality statistics.
Those who think that design and training will make them safe would do well to
consider whether they really have the aptitude, focus and objectivity required.
Not being an anal retentive, schizophrenic, gearhead, nerd is not exactly a
failing and being wrong about it involves a very big bet with dire consequences
for sundry innocent parties."
If going deeper or getting closer to some
fishes is worth the expense, logistics, maintenance, attention, and risk of
rebreather diving only you can decide. If in doubt give it a miss and spend the
extra time saved in carefree diving with ordinary scuba. You won't lose
much in the tradeoff.
For a good general discussion on rebreathers see:
For more on Rich Pyle's work
see: The Coral-Reef Twilight Zone