The World's Columbian Exposition 1893. Chicago, U.S.A. 1893
Official Catalogue With Illustrations issued by the Royal Danish Commission

HISTORICAL NOTES U5 Niels Stensen. theories were founded on observations and measurements, new instruments partly of his own in- vention, while before him all astrono- mers — Copernicus not excepted — had been reasoning rather than observing. At Uranienborg Tyge Brahe laid the foundations of modern astronomy whose speedy and direct fruit the laws of Keppler were. But not only astronomy owes its progress to Danish studies. Alexander Humboldt gives another Dane the name of the creator of geology, viz., the learned Niels Stensen or, as his .s, Nicolaus Steno (1638—1686). He first drew upon himself the attention of the learned world by pro- minent anatomical discoveries touching the glands and the muscles, the heart and the brain. But later on, in 1669,. he writes a book where he, as the first, points out the different strata of earth, the older formations without objects of antiquity and the younger ones containing these objects. This book was published at Florence where, moved by religious scruples, he embraced the catholic faith. In his later days he gave up science altogether finishing his useful life at Schwerin as bishop in partibus and apostolic vicar in the North. We now pass to the discoverer of the velocity of light, Prof. Ole Rømer (1644—1710). In the year 1671 a 10