ground-plan of the house you may obtain for your money. Really these pattern cards of houses are as convenient as a pattern card of buttons. Our space will not permit us to give many examples of these pattern cards, but the two illustrations on the previous page will show to the eye the amount of accommodation a man may obtain for a small monthly payment, together with the land on which it stands, and the grounds around it, as shown in the plan, which the reader may value at its worth. Of course there is a small plot behind these villas, which are semi-detached.
The better portions of the working classes are largely availing themselves of these societies, especially for building purposes; but hitherto the middle classes, including the professional classes, have not done so. There is no reason why this should be; indeed there are some reasons why the manner in which these societies work should be particularly applicable to professional men, as their incomes are generally pretty settled, and their receipts are distributed over the year pretty evenly. Of one thing they may be certain—that the calculations on which the Birkbeck Land and Building Societies are founded are perfectly trustworthy, as they have received the approval of Mr. Tidd Pratt, and of the actuary, Mr. Scratchley, whose authority and trustworthiness in this class of venture are so well understood.
FOSSIL THUNDER AND LIGHTNING.
I can fancy my readers, especially those who have an incipient interest in geology, taken rather aback by the heading of my paper, and imagining that geology must be a more extensive science than they thought for, since it embraces not only things but sounds. Everybody knows what a fossil shell is—it is something palpable and tangible; but fossil thunder and lightning must be a joke on a par with that of the sailor who swore that he once caught a gale of wind and tied it in a knot. I will first take the thunder, which, I may as well confess at once, is a sad misnomer, given in the days when popular science was not. I remember, as a lad, seeing in my father's study a large oval ball, of a dark metallic colour, and covered all over with little bumps, that I always used to call a thunderbolt; and it is with a chat about these that I may, perhaps, interest my reader for a few minutes. What are popularly called thunderbolts are known to chemists and geologists as aërolites, or meteorites—the latter term being given from their supposed connection with meteors and shooting stars. From all ages of the world these aërolites have been invested with a great amount of fascination and mystery, and have been the subject of philosophic speculations from the earliest times; for in the Chinese annals mention is made of upwards of sixteen falls between the seventh century before Christ up to 333 years after Christ. Subsequently the Greek and Roman savans propounded their views on the phenomena, the sage Anaxagoras being of opinion that the stars were masses torn away from the earth by the violence of the rotation, and that the whole heavens were composed of stones. He even suggested that these dark masses of stones, getting between the earth and the moon, produced an eclipse. The general view which has been arrived at by the philosophers of the present day, including that tower of strength Baron Humboldt, is that aërolites are in reality heavenly bodies, which, moving in the space or "cosmos" above, have come within the earth's attraction, been deviated from their course, and arrived in these regions in a high state of temperature. Some have supposed that they are the results of eruptions of the volcanoes in the moon, projected with incredible force so as to pierce the atmosphere of this earth, and thus to be drawn within its attraction.
In both cases the result arrived at appears to be nearly the same, viz., that an aërolite is a foreign body, which has lost its way and come to the earth, though, whether from the moon, or, as an independent heavenly body, doctors differ. The high temperature appears to be a constant accompaniment, and was noticed by Anaxagoras, who observed that the stony bodies were made to glow by the fiery ether, so that they reflected the light communicated to them by the ether. The temperature may be owing to the extreme velocity of the fall of the aërolite, but may also arise from the circumstances under which it is ejected. However that may be, it is one of the most wonderful facts that these bodies, emerging from the heavenly spaces above, can be touched, weighed, and analysed by the creatures of this earth; and still more wonderful to find that they consist of substances identical with substances which we find in the mineral structure of the earth, making it probable, according to the conjecture of Sir Isaac Newton, that the materials which belonged to one group of cosmical bodies are, for the most part, the same. It seems as though analysing a meteorite was like questioning a messenger from the stars, and throws a glow of light on the probable structure of the sister world. When broken, their appearance inside is grey, earthy, or metallic; but the outside is invariably covered by a dark metallic shining crust, produced, perhaps, by a fusion of the constituent elements.