The work of tile late Hermann Vogelsang, and the subsequent researches of O. Lehmann and other observers, have done much to show that a careful study of the rudimentary forms of crystallisation may prove as valuable to the mineralogist as that of embryology has already been to the comparative anatomist.

It is, indeed, difficult to form any clear conception of the manner in which a crystallite originated, nor can we go further back in the history of its development than a stage in which a number of atoms have been grouped in an arrangement about which there is yet no certainty, thus forming molecules grouped in some manner about which we are equally uncertain. We can but imagine that there is some inherent property in molecules which causes them, under given conditions, to group themselves in an orderly manner and to assume a form which may, when more fully developed, be referred to one of the recognlsed crystallographic systems.

In examining a specimen of the rhyolitic lava-flow of the Rocehe Rosse, Lipari, in the collection of the Royal College of Science, London, I was struck by tile fact that the areas of pure black glass visible upon the fractured surface were each bordered by a band of spherulitic matter, the convex surfaces of the spherulites being directed inwards towards tile glassy area. The specimen, collected by Prof. J. W. Judd, F.R.S., evidently comes from a portion of the flow which has become breceiated during movement of the viscid mass; intermingling of glassy and hemicrystalline matter has occurred, and an approach to the structure of the well-known "Piperno" of Naples has resulted. But the irregular little lumps of obsidian have not received their spherulitic crust from any chilling effect that they may have had upon the surrounding groundmass; the spherulites belong to the glass-fragments themselves, and are not deposited upon their surfaces.

Kynance Cove lies in the midst of a Serpentine District. The Serpentine is associated with some little hornblende schist in the cove, and is traversed by black dykes both porphyritic and non-porphyritic from a few inches to several feet thick, by granitic veins, as also by veins of saussuritic gabbro, which latter are, however, of rare occun'ence on the western side of the Lizard.

When looking due east from the middle of Kynanee Sands a rectangular block of white rock is seen in the dark red serpentine cliff from 70 to 80 ft. above the sea-level at low water, and about 200 yds. from the spectator. The vein that gives rise to this block can be easily reached by crossing the stream that enters the cove from the east, climbing the rising ground, and after reaching a ridge about 100 yds. from the stream, descending the grassy slope to the right to a point about 9.00 yds. south-east of Oliver's Refreshment House. Here, a few feet below the grass, a block of rock is seen 4 ft. high, 6 ft. through in front, and covered by broken serpentine behind.

Fresnel's representation of the laws of transmission of rays of light in biaxal crystals, by reference to the surface distinguished by his nsane, has long been regarded as one of the greatest achievements in the domain of Physical Science. In his memoir on Double Refraction, Fresnel proceeded as follows :—

1. He assumed that the transmission of a ray of light is effected by means of an elastic ether vibrating transversely to its direction.

To the ether is thus assigned a property not belonging to a perfectly fluid body in a state of rest : perfect fluidity of a body at rest involves incapacity of resistance to mere change of shape, and it is to such distortional resistance that transverse vibrations must be due.

About two years ago Mr. T. A. Herstand of Mainton Springs, Colorado, made a remarkable find of tysonite and bastnäsite at Crystal Park, near Malnten Springs, Colorado. The entire find consisted of one crystalline cleavable mass of tysonlte, covered with bastnäsite, weighing in all fully six kilograms. It was found in a coarsely crystalline granite, and no other deposit has been discovered subsequently, although considerable search has been made by various prospectors. Up to the time of this find all the tysonite discovered in Colorado has not amounted to more than 50 grams.

The tysonite was Principally of a rich cinnamon-brown colour with a perfect basal cleavage, and frequently contained patches from one to three cm. in diameter which were entirely transparent.