Om Materialprøvningens Udvikling i Norden
Og om Statsprøveanstaltens Virksomhed

132 increase very much in size, which is proved by the curve pas- sing into an abruptly downhill branch. The Laboratory- has made some experiments with F ere t cement prisms to institute a comparison with the common standard tests, especially for determining the influence on the strength of different additions of water and different stamping of the prisms. A report of some of these experiments, has been sent to Prof. Schule in Zurich, the chairman of the Committee 42. The Sub-Director in charge of the Laboratory, Mr. Mayntz Petersen, has already before the Congress of Brussels, made some experiments for the committee 30 for determining the q u a n t i ty of fine particles in cement, see Professor Gary’s report to the Brussels Congress; the experiments, which have been executed for the Association of Scandinavian Manufacturers of P o r 11 a n d c e m e n t, have later been completed, and report has been given to Prof. Gary for the use of his discourse at the Congress in Copenhagen. Assisted by the Laboratory the same association has as early as 1896 commenced a series of experiments on th e resistance of cement mortar to the influence of the sea wate r, for which 4000 cubes were produced by the Labora- tory and immersed in different places of the Scandinavian seas. On the part of the said association Mr. A. Poulsen, chief-engineer at the Hydraulic Engineering Department in Lemvig, will give an account at the Congress in Copenhagen of the results obtained up to this time. The Congress of Brussels had resolved that the test for determining the normal consistency should be made in a mould inside conical with 400 g cement in a way the details of which were given more particularly. It has, however, appeared from the experiments of the Laboratory, that this quan- tity of cement is rather small, which has been further strengthened by experiments made by Prof. Mesnager, wherefore the Laboratory intends through Sub-Director Mayntz Petersen to place before the Congress in Copenhagen the question of an amendment in the rules agreed upon in Brussels as to this point. At the Laboratory various other researches have been made on cement, for instance, on the faculty of cement mortar in pro- tecting iron structures from fire. Some other experiments made for Mr. Grat, Captain of the Royal Engineers, on the strength of