b. ? 1753 and d. November 22, 1824

French naturalist. In 1780 he explored South Africa, extending his researches northward beyond the Orange River. He remained in Africa till July, 1784, and made a large collection of African birds. He published a “Natural History of the Birds of Africa” (1796-1812).

 Nor these alone possess the lenient power
 Of soothing life in the desponding hour.
 Some favorite studies, some delightful care,
 The mine with trouble and distresses share;
 When of some pleasing, fancy good possessed,
 Each grew alert, was busy, and was blessed.
 Whether the call-bird yield the hour’s delight,
 Or-magnified in microscope-the mite;
 Or whether thumblers, croppers, carriers seize
 The gentle mind, they rule it and they please.

 —Rev. George Crabbe

 Mark it all, within, without!
 No tool had he that wrought,
 No nail to fix, no bodkin to insert,
 No glue to join; his little beak was all:
 And yet how neatly finished! What nice hand,
 With every implement and means of art,
 Could make me such another? —A Bird’s Nest: J. HurdisJ. Hurdis 1722, May 11-1789, April 7—Pieter Camper lived. He filled successively the chairs of philosophy, anatomy and medicine at Amsterdam and Groningen. In 1771 he discovered the presence of air in the bones of birds. Among his works are “Anatomico-Pathological Demonstrations” (1760-1762) and “The Sense of Hearing in Fishes.”

J. Hurdis 1722, May 11-1789, April 7—Pieter Camper lived. He filled successively the chairs of philosophy, anatomy and medicine at Amsterdam and Groningen. In 1771 he discovered the presence of air in the bones of birds. Among his works are “Anatomico-Pathological Demonstrations” (1760-1762) and “The Sense of Hearing in Fishes.”

b. February 4, 1859 and d. November 22, 1896

American engineer. He worked as a civil engineer in West Virginia and Kentucky. He conceived the idea of building the gigantic revolving wheel known by his name, which was a conspicuous figure at the Columbian Exposition in Chicago, in 1893.

 I’ll build it so, that if the blast
 Around it whistle loud and long,
 The tempest when its rage has pass’d
 Shall leave its columns doubly strong.
 I’ll build it so, that travelers by
 Shall view it with admiring eye,
 For its commodiousness and grace:
 Up from the ground-straight to the sky-
 A view of earth, from God’s dwelling plav=ce.

 —Adapted from The Building of the House: Mackay

 The largest pyramid, Ghizeh, is 461 feet high; the Sphinx, near to it, 100 feet; the Colossus of Rhodes was 106 feet; the Ferris Wheel, 264 feet; the Eiffel Tower of the Paris Exposition, 984 feet; the Washington Monument, 555 feet in height. The last was designed by Robert Mills and built by Lieut, Colonel T. L. Casey. The highest building in New York, the Park Row Syndicate, is 382 feet high.

 1871, June—The Tay Bridge was begun in Scotland; May 31, 1878, it was opened; length, 10,610 feet; consisted of 85 spans, some 90 feet above water level; cost £350,000; about 20 lives lost during its construction.

 1889, March 31—Eiffel Tower in the Champ de Mars, Paris, was completed. 984 feet high; 7,000 tons iron used; cost over $1,000,000.

b. February 12, 1804 and d. November 21, 1885

American mathematician and inventor. 1853-1858 he edited the Railroad Times and invented and constructed a spike-making machine, a water-faucet and an improved pipe-coupling. He evolved a new formula for finding the values of policies of various terms, known as the “accumulation formula,” and invented and patented (1869) the arithmeter, a mechanical contrivance for arithmetical operations based on logarithms. He published several works on practical insurance.

 The chiefest action for a man of spirit
 In never to be out of action; we should think
 The soul was never put into the body,
 Which has so many rare and curious pieces
 Of mathematical motion, to stand still.

 —Devil’s Law Case: Webster

 500-1150—The Hindus invented a process of casting out nines and they were familiar with the rule of three, with computation of interest with allegation and arithmetical and geometrical series.

 1299—The Florentine merchants were forbidden the use of Hindu numerals in bookkeeping and either to use the Roman numerals or to write the numbers in words.

 1501-1576—Jerome Cardan lived. He was a believer in astrology and pretended to have calculated his own death. He published “Ars Amgna,” which was remarkable for the age and in which were some of Tartaglia’s rules.