Transactions of the American Ceramic Society containing the papers and discussions of the annual meeting Volume 11 - Tapa blanda

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1909 Excerpt: ...and practice have, in a measure, confirmed this, but I must confess that just what was the cause, and where to find a reasonable explanation of this peculiar phenomena from a scientific standpoint, 1 am as vet unable to answer with certainty. CLARIFIERS, DECOLORIZERS, ETC. Regarding these materials, there is not much of importance to say from a physical standpoint, other than color. Arsenic, which is used as a clarifier, does increase the crushing strength somewhat, but it is seldom found in the finished metal in sufficient quantity to be noticeable, and the same is true of manganese. Cryolite, which is used sometimes as a clarifier, is of but little value, and is somewhat detrimental to the furnace or pots, owing to the liberation of fluorine. It would he of some value, could it be used in sufficient quantities to introduce enough alumina to be of importance, but this cannot be done without producing stones, or opal glass. One frequently hears the remark that a chemist or scientist is of no use in a glass factory. This, no doubt, in a measure is true, for it is seldom, if ever, that a chemist or scientist will be able to find a manufacturer or owner, who would for a moment think of wasting time or money in the consideration or adoption of the suggestions of such individuals, at least not until they are confronted with a situation that legend, sorcery, prejudice and guess work can not account for or overcome. In addition to the composition and ingredients, consideration must also be given to the fact that melting conditions have a great iufiueuce on the physical properties of glass, and the following will give some idea as to the extent. Pour melts were made from the same batch, under the same conditions, and all, when finished, had the same general appeara...