It was a great triumph to the American biologists who had at last added heads to the bodies, and very formidable heads too. It was no less a thrill to Professor Griffith Taylor, Sir Charles Wright and myself to hear of the discovery, since we were the trio who discovered the last of the headless fish in 1911. In fact, Sir Charles happened to be in the Antarctic again last year and he sent me a Christmas card bearing the words: ‘Some Fish! ! ! ‘
The accompanying map shows the position of the McMurdo Ice-Sheet lying under the shadow of Mount Erebus and close to Captain Scott’s base of 1902-3, which is now the headquarters of the American Operation Deep Freeze. It shows also that the sheet is really a confluence or coalescence of the Koettlitz Glacier, coming down from high mountains, with an offshoot of the Great Ross Ice-Shelf, which has found its way between two large volcanic islands. The combined sheet, some forty miles wide, moves slowly up the Sound, afloat.
Now, on the Ross Ice-Shelf there is a yearly increment of a foot of snow, so that anything on it is quickly buried. In fact the grave of Captain Scott and his companions is already fifty feet below the surface, travelling about a mile a year towards the front of the Shelf where it will break off in an iceberg a century hence.
The McMurdo Ice-Sheet, on the other hand, behaves quite differently and any material on its surface remains uncovered because the summer’s thaw exceeds the winter’s snowfall.
As may be seen in the photographs, the terrain explains why the fish and the sponges have remained unvisited for so long. The central belt of the moraine-strewn sheet, known as the Pinnacled Ice, when not referred to in much more lurid language, has rarely been traversed by sledgers unless there is no other way round. The scenery is fascinating but the going is execrable, bad for sledges and ruinous to the temper. It might be called relict ice, what is left after the summer’s thaw has melted away the ice wherever it is in contact with black gravel warmed by the sun. It has produced a sort of miniature scenery of mountains and valleys, of grottoes and tunnels, and, for a brief week each year, a network of rushing streams up to two feet deep, threading their way to the sea. It is best described by quoting from the diary of Dr Edward Wilson when he first crossed it: ‘All this old pinnacled ice was strewed with wind-blown sea-wrack as well as with stones and gravel, glacier-borne. We found from time to time shells, sponges and dead fish, even the longest Notothenia—four feet long—always without a head. Three of these fish we found, but not one had a head.’
The helicopter has changed all that and probably the Americans take only half an hour to reach our holiday apartments Madrid whereas it took us five days.
To show how widespread are the scattered remains of sponges, battered by centuries of blizzards, it is worth mentioning that anywhere in the pinnacled ice it is difficult to get ice for cooking which has not got myriads of tiny sharp needles of sponge spicules in it. These are not apparent until they appear as a mesh on the bottom of one’s pot of hoosh, or on one’s tongue.
The centre of interest in this recent discovery has naturally been the flats for rent Edinburgh rather than the apartments in Porto, both on account of their size and of the situation in which they are found. In point of fact, however, the sea-bottom material is more important, as it could not by any means have removed itself, whereas the fish could conceivably have gone by some strange route.
Any hypothesis put forward to account for these objects in unexpected places must account for all the facts, as is done in the best of detective stories, not only for a selected few of them. It is easy enough to suggest, as does our theory, that the ice-sheet freezes onto the bottom and the material finally reaches the top because of loss by thaw above and more freezing below. But what about those long thin spicules on the sponges and the still more delicate solitary coral? How are they to be preserved from harm while being frozen onto the base of a sheet weighing millions of tons and subject to hinge-movements of tides?