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A small beginning has led us to a great ending.  If I were to put the bit of chalk with which we started into the hot but obscure flame of burning hydrogen, it would presently shine like the sun.  It seems to me that this physical metamorphosis is no false image of what has been the result of our subjecting it to a jet of fervent, though nowise brilliant, thought to-night.  It has become luminous, and its clear rays, penetrating the abyss of the remote past, have brought within our ken some stages of the evolution of the earth.  And in the shifting “without haste, but without rest” of the land and sea, as in the endless variation of the forms assumed by living beings, we have observed nothing but the natural product of the forces originally possessed by the substance of the universe.

[Illustration]

A BIT OF SPONGE

(Written on Scotland.)

(FROM GLIMPSES OF NATURE.)

BY A. WILSON.

[Illustration]

This morning, despite the promise of rain over-night, has broken with all the signs and symptoms of a bright July day.  The Firth is bathed in sunlight, and the wavelets at full tide are kissing the strand, making a soft musical ripple as they retire, and as the pebbles run down the sandy slope on the retreat of the waves.  Beyond the farthest contact of the tide is a line of seaweed dried and desiccated, mixed up with which, in confusing array, are masses of shells, and such olla podrida of the sea.

Tossed up at our very feet is a dried fragment of sponge, which doubtless the unkind waves tore from its rocky bed.  It is not a large portion of sponge this, but its structure is nevertheless to be fairly made out, and some reminiscences of its history gleaned, for the sake of occupying the by no means “bad half-hour” before breakfast.  “What is a sponge?” is a question which you may well ask as a necessary preliminary to the understanding of its personality.

[Illustration:  A SPONGE ATTACHED TO ITS ROCKY BED.]

The questionings of childhood and the questionings of science run in precisely similar grooves.  “What is it?” and “How does it live?” and “Where does it come from?” are equally the inquiries of childhood, and of the deepest philosophy which seeks to determine the whole history of life.  This morning, we cannot do better than follow in the footsteps of the child, and to the question, “What is a sponge?” I fancy science will be able to return a direct answer.  First of all, we may note that a sponge, as we know it in common life, is the horny skeleton or framework which was made by, and which supported, the living parts.  These living parts consist of minute masses of that living jelly to which the name of protoplasm has been applied.  This, in truth, is the universal matter of life.  It is the one substance with which life everywhere is associated, and as we see it simply in the sponge, so also we behold it (only in more complex guise) in the man.  Now, the living parts of this dried cast-away sponge were found both in its interior and on its surface.  They lined the canals that everywhere permeate the sponge-substance, and microscopic examination has told us a great deal about their nature.