Page:Popular Science Monthly Volume 7.djvu/132

122 found the water taken from 750 fathoms depth, and just above the ooze upon the bottom, turbid from the presence of multitudes of young Globigerinæ. The evidence is satisfactory to him that they live and propagate on the sea-bottom, as well as near the surface—that the young rise to the surface in the earlier stages of their existence, and become inhabitants of the upper waters, and in their adult stage sink to the bottom in consequence of the increasing thickness of their shells.

The cause of their sinking, therefore, is not death of the creatures, but weight of their shells. The thickening consists in a deposit of calcareous matter upon the outside of the proper wall after the creatures' full growth, which not only increases the weight, but alters the contour of the shell.

Prof. Carpenter cites the fact, noticed by himself, that, in cold areas of the sea-bed north of Scotland, no Globigerinæ were found, while the warm areas adjoining are covered with this peculiar ooze to an unknown depth. Why is this, he asks, if the surface only is their habitat, where the temperature of the cold and warm areas is the same?

Priestleyana.—The recent celebrations at Northumberland and Birmingham of the centenary of the discovery of oxygen by Dr. Priestley brought out many curious incidents in his career, and numberless anecdotes; we select the following as characteristic:

While he was minister at Leeds, a poor woman, who labored under the delusion that she was possessed by a devil, applied to, him to take away the evil spirit which tormented her. The doctor attentively listened to her statement, and endeavored to convince her that she was mistaken. All his efforts proving unavailing, he desired her to call the next day, and, in the mean time, he would consider her case. On the morrow the unhappy woman was punctual in her attendance. His electrical apparatus being in readiness, with great gravity he desired the woman to stand upon the stool with glass legs, at the same time putting into her hand a brass chain connected with the conductor, and, having charged her plentifully with electricity, he told her very seriously to take particular notice of what he did. He then took up a discharger and applied it to her arm, when the escape of the electricity gave her a pretty strong shock. "There," said she, "the devil's gone; I saw him go off in that blue flame, and he gave me such a jerk as he went off! I have at last got rid of him, and I am now quite comfortable."

The destruction of Dr. Priestley's house and laboratory, by the riotous mob, at Birmingham in 1791, proved most disastrous, and the maddened crowd met with little opposition. "There was a small attempt by a few people to drive off the rabble, but they were compelled to show their heels by a shower of brickbats." The following amusing doggerel poem, which was published at the time, refers to this incident:

The following epitaph, having reference to Dr. Priestley's peculiar religious views, was composed, before his death, by Rev. David Davis, one of the wits of the time. Dr. Priestley is said to have laughed heartily over it.

Effects of Compressed Air.—From Bert's researches it appears that meat does not oxidize and putrefy in compressed air merely undergoing a change of color, consistency, and taste. But, on the other hand, muscular and nervous excitability disappear very rapidly in compressed air.