Om Materialprøvningens Udvikling i Norden
Og om Statsprøveanstaltens Virksomhed

140 for instance, display a resistance to crushing of only 18-—29 kg pr. sq. cm. Moler bricks can be employed for partitions ma- soned directly on the floors without any other support than the latter and for floor-constructions and for vaults of every form. When used for vaults between iron-beams, the latter can be made less strong than on employing common bricks. As the bricks can be rendered nail-proof they can likewise as »Schwemmsteine« be employed for the fastening of the frames of doors. In the brick- field of Vindø were produced special bricks for the masoning of chimney corners in a line with partitions of boards. On account of the ligthness of the moler bricks, it is possible to employ bricks of the double height without their becoming heavier than common bricks. Thus the number of joints is decreased, less lime is em- ployed, and piling, loading and unloading becomes easier. That moler bricks of the usual size are very comfortably managed by masons and labourers, and that twice the number can be loaded on railway-cars and lighters goes without saying. Apart from being adapted to bricks of partitions moler bricks can be employed in the masoning of boilers, but not instead of fire-proof bricks, nor as outer bricks owing to their prominent water absorbing properties. (Nor are they, for the same reason, suitable as nether bricks in buildings). But their being bad conductors of heat renders them well fit for being placed elsewhere in the boiler-masonry. The slight thermal conduc- tivity has been substantiated by various experiments, both at the Testing Laboratory and in the Eastern Gas-Works, where the ma- nager Mr. Irminger placed some bricks as cover of the retort- bench above a retort comparing them with two different sorts of fire-proof bricks and common bricks. In the new poor-house »Sundholm« in Copenhagen, the chief-engineer in the municipality has had quite uniform boilers masoned both with and without moler bricks, so that it can be established by means of experi- ments also there, whether moler bricks are well adapted to the isolating of heat. Another competent authority has, for the rest, written a warm recommendation for moler bricks having proved excellent for boiler-masonry1). The slight thermal conductivity in the moler brick is, of Annual Report of the Laboratory for 1907, p. 6. ■ "rÆ.A ....