Om Materialprøvningens Udvikling i Norden
Og om Statsprøveanstaltens Virksomhed

172 influence in a totally natural way will afford great difficulties at laboratory experiments, so great, that the Laboratory did not think itself able to overcome them without the experiments be- coming too expensive. In the Report X treating of the experiments an account is first, rendered why fresh cement-plaster attacks oil-paint, so that 1 and 2 years ought generally to pass before the plaster is painted in oil, and then the methods are enumerated by which the named in- jurious influence can be counteracted. Finally the materials are treated of which have been used for the experiments, and how the latter were executed both in fresh surface-dry cement-plaster, and in fresh, moist cement-plaster. As result of the experiments shall be named here that among the half score of materials tested the socalled Fluociment, invented by Kessler, was found to be the best for painting on fresh cement-plaster when surface-dry for which was, however, required an age of no more than a few weeks, while the socalled K a u t- s c k u k b u 11 e r from Chemische Fabrik Busse, Hannover—Lin- den, was found to be best for fresh, moist cement-plaster and for the rest also very good in fresh surface-dry cement-plaster. In the treatise are finally mentioned some other materials who are in the market for the same use, but were not embodied in the series of experiments. The experiments treated of under f occasioned Ihe Laboratory to paint on plaster with cement and lime colours, for instance, to paint with a compound of cement and colour and render the paint washable in treating it with fluate. On this occasion Miss Kling- berg, at that time assistant of the Laboratory, tried to replace fluate by a diluted dissolution of oxalic acid or a concentrated dissolution of oxalate of ammonia, as, for instance, ultramarine coloured plaster cannot stand oxalic acid, but very well oxalate of ammonia, and she employed these materials not only for painting on cement but also for painting on lime to render the painting washable. More particular details on this occur at the end of Report VI of the Laboratory. i. Researches on Linseed Oil and Rust-preventing materials. These researches were made for the Church and School De- partment and published in Report XII. The first part treating of researches on linseed oil was the object of a discourse delivered