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The morning of the 29th of March, 1909, a heavy and dense fog of frost spicules overhung the camp. At four A. M., the Captain left camp to make as far a northing as possible. I with my Esquimos followed later. On our way we passed over very rough ice alternating with small floes, young ice of a few months' duration, and one old floe.
It seemed marvelous to us that birds so moderate in size could hold so much of this wonderful song stuff. Each one of them poured forth music enough for a whole flock, singing as if its whole body, feathers and all, were made up of music, flowing, glowing, bubbling melody interpenetrated here and there with small scintillating prickles and spicules.
The spicules are some crutch-like, others spined or echinated, while the deep-sea sponges appear to grow long thick spicules, which attach the sponge to the ground by means of grapnel-like ends. In some cases the skeleton seems to be more or less replaced by sand, the small grains of which are cemented together by the "spongin." Dr.
The specimen was, indeed, pretty in more than a technical sense. Mingled with crystalline grains of quartz, glassy spicules, and water-worn fragments of coral, were a number of lovely little shells, some of the texture of fine porcelain, others like blown Venetian glass. "These are Foraminifera!" I exclaimed. "Yes." "Then it is not silver sand, after all?" "Certainly not." "But what is it, then?"
In the end of this bone we find a net-work or scaffolding, wonderfully constructed and composed of delicate spicules and lamellæ. The whole is so arranged that with the least expenditure of material the most effective action on the joint-surfaces is obtained—hence the most efficient distribution of friction and a proper freedom of movement.
X-ray appearances in periosteal tubercle: the surface of the cortical bone in the area of disease is roughened and irregular by erosion, and in the vicinity there may be a deposit of new bone on the surface, particularly if a sinus is present and mixed infection has occurred; in syphilis the shadow of the bone is denser as a result of sclerosis, and there is usually more new bone on the surface hyperostosis; in periosteal sarcoma there is greater erosion and consequently greater irregularity in the contour of the cortical bone, and frequently there is evidence of formation of bone in the form of characteristic spicules projecting from the surface at a right angle.
Mixed with the Diatoms there were a few small Globigerinoe, some of the tests and spicules of Radiolarians, and some sand particles; but these foreign bodies were in too small proportion to affect the formation as consisting practically of Diatoms alone.
On the second day we crossed "Death Valley," so called because two men were once found frozen in it; a bleak, barren expanse, five or six miles across, with a great gale blowing right down it, charged not only with particles of hard snow but with spicules of ice and grains of sand.
As I trampled through the grass the frost spicules from the tussocks I brushed against filled the spaces between the leather and my feet. I began to suffer excruciating pain. I thought day would never break. My feet felt as though they did not belong to me. Soon they ceased to be painful, but the pain-area had traveled up my legs.
Where sponges and other silica-secreting organisms abound on limestone banks, silica forms part of the accumulated deposit, either in its original condition, as, for example, the spicules of sponges, or gathered into concretions and layers of flint.
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