A "DRY-MAKING" IN HOLLAND.
The conversion into solid land of the Lake of Beemster, in North Holland, is, after the Haarlemmermeer Polder (which is twice and a half its size), the largest specimen in the Netherlands of what the Dutch term "dry-makings." The scheme was first broached in 1570. In 1592 funds were applied for, which were not, however, promised by the States of Holland and West Friesland until 1597. In 1607, a company was formed at the Hague, by Dirck van Oss and others, to pump out the Beemster in whole or in part; and on their security the States lent the necessary capital. At the commencement, it was thought that sixteen windmills would suffice for the undertaking; but this number was shortly increased by ten, and the twenty-six mills were then divided into thirteen gangs. By the end of 1608, several of the mills began to pump, and early in 1609, they were all ready. Towards the end of this year, the bottom of the lake became visible in some places: but during a storm on the 23d of January 1610, the great waterland sea dyke gave way, and the pressure on the ring dyke that had been constructed round the Beemster proved greater than it was capable of resisting. It gave way in turn in two places, and the lake was again filled. On the 5th February 1610, further and ample funds were advanced by the States; in 1611, more mills were put on to the work; on the 19th of May 1612, the dry-making was at last completed; and on the 30th July of that year, the distribution of the lots of land redeemed took place. The ring dyke is over 37,000 yards long, and has an average height of × 1·50 Z. P. (a metre and a half above the mean level of the sea). Thus was the Beemster pumped out; and from that day to the present, the name of Dirck van Oss has been held in deep respect in Holland, as the name of the first Dutchman who conquered the waters on anything like a large scale. The system he employed has been closely followed in all successive undertakings of this kind; and, with the exception of the application of steam, and certain improvements in machinery, the plans of Dirck van Oss for draining the Beemster were adapted with a like success to the Lake of Haarlem, by M. Gevers d'Endegeest, the hero of this last conquest, and the sanguine prophet (1867) of the ultimate reclamation of the Zuyder Zee. The drainage of the Lake of Haarlem, it may be mentioned, was accomplished in 1852, after thirteen years of toil and anxiety, at a cost of 11,000,000 florins (£916,666); a sum which, large as it is, has nevertheless been completely recovered, both in capital and interest, by the sale of 42,481 acres of arable land.—Report to Foreign Office.
A SCIENTIFIC PILGRIM.
When Lord Napier (of Merchiston) first published his Logarithms, Mr. Briggs, Professor of Mathematics at Gresham College, London, was so surprised with admiration, that he could not rest till he had seen the noble inventor, and actually went to Scotland for that purpose in 1615. Lilly, the astrologer, thus describes the interview:—"Mr. Briggs appointed a certain day when to meet at Edinburgh; but, failing thereof, Merchiston was afraid he would not come. It happened one day, as John Marr and the Lord Napier were speaking of Mr. Briggs: 'Ah! John,' said Merchiston, 'Mr. Briggs will not come.' At the very instant, one knocks at the gate; John Marr hastens down, and it proved to be Mr. Briggs, to his great contentment; he brings Mr. Briggs up into my Lord's chamber, where almost one quarter of an hour was spent, each beholding the other with admiration before one word was spoken. At last, Mr. Briggs began, 'My Lord, I have undertaken this long journey purposely to see your person, and to know by what engine of wit or ingenuity you came first to think of this most excellent help unto astronomy, viz. the logarithms; but, my Lord, being by you found out, I wonder nobody else found it out before, when now, being known, it appears so easy.'" Briggs was nobly entertained by Lord Napier; and every summer after, during his lordship's life, this venerable man went to Scotland purposely to see him.
THE BURNING MIRRORS OF ARCHIMEDES.
Many have questioned the facts recorded by several historians, concerning the surprising effects of the burning mirrors of Archimedes, by means of which the Roman galleys besieging Syracuse were consumed to ashes. Descartes, in particular, discredited the story as fabulous; but Kircher made many experiments with a view of testing its credibility. He tried the effect of a number of plane mirrors; and, with five mirrors of the same size, placed in a frame, he contrived to throw the rays reflected from them to the same spot, at the distance of more than 100 feet; and by this means he produced such a degree of heat, as led him to conclude that, by increasing their number, he could have set fire to inflammable substances at a greater distance. He likewise made a voyage to Syracuse, in company with his pupil Schottius, in order to examine the place of the alleged transaction; and they were both of opinion, that the galleys of Marcellus could not have been more than thirty paces from Archimedes' mirrors.
M. Buffon also constructed a machine, consisting of a number of mirrors, by which he seems to have revived the secret of Archimedes, and to have vindicated the credit of history in this respect. His experiment was first made with twenty-four mirrors, which readily set fire to combustible matter composed of pitch and tow, and laid on a deal board at the distance of seventy-two feet. He further pursued the attempt by framing a kind of polyhedron, consisting of 168 pieces of plane looking-glass, each six inches square; and by means of this machine, some boards of beech-wood were set on fire at the distance of 150 feet, and a silver plate was melted at the distance of 60 feet. This machine, in the next stage of its improvement, contained 360 plane mirrors, each eight inches long and six broad, mounted on a frame eight feet high and seven broad. With twelve of these mirrors, light combustible matter was kindled at the distance of twenty feet; with forty-five of them, at the same distance, a large tin vessel was melted, and with 117, a thin piece of silver. When the whole machine was employed, all the metals and metallic minerals were melted at the distance of twenty-five and even of forty feet. Wood was kindled in a clear sky at the distance of 210 feet. M. Buffon afterwards constructed a machine which contained 400 mirrors, each six inches square, with which he could melt lead and tin at the distance of 140 feet.