E;*+ - Geological Curators

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THE BURNT DOPE TECHNIQUE
AND OTHER INTER'TIDAL PLOYS FROM AMERICA
Most vertebrate fossil collecting takes place under conditions that are
extremely dry (as in the Wild West) or extremely wet (as in Florida springs).
For these circumstances ingenious collectors have, over the years,
developed techniques for cementing and solidifying the bones so that they
can be extracted and transported with a minimum of damage. A rather
different methodology, however, has had to be developed by those of us who
collect as beachcombers, prospecting the intertidal zone --- what Marlow
called
"...that uncertain shore
That is nor sea nor land,
But changeth as the ocean ebbs and flows."
The bone-bearing formations of the intertidal zone may be well consolidated,
like the soft reddish-brown sandstones of the Triassic around the Bay of
Fundy in Nova Scotia, or they may be unconsolidated like the Cretaceous
greensand in the banks of the Chesapeake and Delaware Canal in Delaware. In
either case the fossils will seldom be dry enough to be handled by the
techniques familiar to arid-country collectors: they will be damp at best
and sopping wet at worst.
An additional complication, and one which gives intertidal collecting
its sporting character, is the time factor. If fossils exposed by the
ebbing tide are given a chance to dry in the sun, it inexorably follows that
the tide will be coming in while the work of excavation is going on. Even
if a bone can be extracted before Neptune takes it again to his bosom, the
collector always runs the risk of having to make his escape by wading around
the point or climbing the cliff.
Around the Minas Basin (the cul-de-sac of the Bay of Fundy) the usual
differences between low and high tide is about 40 feet, and we have
experienced (as Jerry Case can testify) tides as high as 48 feet. As a
result the collector is always digging faster than prudence would dictate,
always tempted to take shortcuts as the wavelets ripple closer and closer
to his feet.
For consolidating damp specimens the intertidal collector's salvation is
the Bumt Dope Technique invented by Stan Olsen ---excuse it, Professor
Stanley J. Olsen ---a former preparator who has ascended to higher rungs
of the scala naturea. Because it has been published only in an out-of-the-way
place (Carroll et al., 1972, p. 24-25) this technique is still unknown to many
who might profit by it. In essence it consists of applying cellulose
cement ("dope") in the usual dry-country manner and then flafning off the
so lven t.
Any acetone -or alcohol-based cement can be used: Duco, Alvar, Ambroid,
or celluloid dissolved in acetone. The trick, as experienced collectors know,
is to make the dope thin enough -- "the consistency of Drambuie but twice
the proof" is a good rule-of-thumb. This elixir is applied liberally to the
specimen and surrounding matrix with a medicine dropper or squirt-bottle.
A small lighter-fluid can with a swivelling plastic nozzle is also handy,
but keep a couple of glass-headed basting pins in your lapel! to clear the
nozzle when it clogs. A match is then applied to the surface, and an old
felt hat is clapped over the little blaze to protect it from the Fundy
breeze until it bums itself out. (Small charred areas only make my
60year-old field hat look more picturesque. NB, a straw hat is not
recom ended for this operation. )