Om Materialprøvningens Udvikling i Norden
Og om Statsprøveanstaltens Virksomhed

'M 106 etc. 1798, that Galileo was the first who tried to utilize the laws of mechanics on the resisting power of solids. When Galileo visi- ted the Arsenal in Venice, he saw in the different workshops the machines they constructed, and from that time he began ponde- ring upon this power of resistance. Galileo easily perceived that a cylinder when suspended perpendicularly would draw itself over at the weakest spot and further1) that it would be influ- enced quite differently if it was placed horizontally with one end in a wall. He made a formula, although not quite correct, of the strains it would be subjected to in the cross-section which lies in the plane of the wall. He further found that a rectangular beam was stronger when placed on edge than when on the flat. He also took to calculate how a beam fixed in one end should be formed to contain as little material as possible in the diffe- rent cross-sections and found out that the underside being hori- zontal the topside ought to be formed after a parabola. Frémont further points out that Galileo, who died on the 8th of January 1642, 77 years old, and who never omitted to call people’s attention to the practical use of the results he arrived lo, did not however make real experiments of tes- ting materials. Fremont writes, quoting Girard, that the first experiments seem to be due to a Swede P. Wurtzius as it ap- pears from a letter to him in 1657 from Francois Blondel the French architect, who after Galileo is the first author who writes about these matters and who says himself that he was one of the last of Galileo’s pupils2). Through the publication of Leonardo da Vinci’s large, hitherto unpublished, manuscript »Codice atlantico3), which dates from about 1500, it appears however, that already Leonardo has made experiments on strength, Galileo, thus, not being the first who has written about such experiments, and Wurtzius not the first who has executed such experiments. But Leonardo’s experiments which for instance treated of the deflection of beams when subjected to different loads, have hardly gone so for as to practically test the accuracy of the str eng th- calculations, or to employ them practically. From Galileo’s most celebrated work on mechanics: Discorsi e dimostrazi- oni matematiche etc. 1638. 2) The undermentioned letter from Blondel to Sieur B. pag. 166. 8) See Prof. Th. Beck’s treatise in Zeitschr. des Ver. deutsch. Ing. 1906, p. 524