Om Materialprøvningens Udvikling i Norden
Og om Statsprøveanstaltens Virksomhed

■ ... ; ' ' -.'V;?i,; 148 through 25 freezings with ensuing thawings. Each freezing lasting at least 4 hours took place at a temperature of 10 to 12° Centi- grade below zero, each thawing lasting about 2 hours look place in water of about 20° Centigrade. The outcomes for the individual sorts of bricks follow below. Sort A. Each and all of the bricks were damaged, 4 being more severely corroded, 6 displaying a less important or very slight injury. The bricks, tested for resistance, had suffered too much to be tested for compression. Sort B. 3 bricks were a little damaged, the other 7 undamaged. Compression-tests with the bricks that had gone through the test of resistance to frost proved the average resistance to crushing to be 241 kg pr. sq. cm. Sort C. 8 of the bricks were very much, 2 rather slightly damaged. No compression-tes t s could be made, the bricks having suffered too much from the test of resistance to frost. Sort D. The bricks No. 1—7 and No. 9 had been very much damaged. The bricks No. 8 and 10 but slightly. These bricks could not be subjected to compression-tests having suffered Loo much from the preceding test. ß. Sand-Lime-Bricks Tested as to their Resistance to Frost by Special Methods. Those tests of resistance to frost of which the question is here, were first undertaken at the factory itself, and then the Laboratory repeated the experiments as a control, and an account is rendered here only of the own experiments of the Laboratory. They were made with 8 bricks of each sort. The 4 bricks were clasped into iron straps such as it is displayed at p. 51 by fig. 16. Thus free evaporation could take place from all the surfaces of the bricks. To keep them separated small