Porcelain square-n-triangle for the support of a crucible and its lid

In gravimetric analyses, whenever partial covering of the crucible is required during the ignition of a filter paper containing a precipitate, our stu...
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A Porcelain Square-n-Triangle for the Support of a Crucible and its Lid In gravimetric analyses, whenever partial covering of the crucible is required during the ignition of a filter paper containing a precipitate, our students have experienced difficulty in keeping the lid on the crucihle. This is particularly the case when the crucible is kept in a tilted position to allow for the ready access of air during the ashing of a filter paper. Due to a lack of sufficient support the lid usually slides off the crucible on to the bench and breaks mining the experiment. Even if the lid survives the fall, the dirt it collects on coming in contact with the bench top causes serious interference in gravimetric analyses. To circumvent the above problem, we have designed s porcelain support for the crucible as well as the lid. The support, which is shown in the figure, can he easily constmded from two regular porcelain triangles as follows: Open one of the parcelsin triangles a t one of its corner and spread the two sides to form a "square U". Arrange this over the second porcelain triangle, such that they together fonn a porcelain square and a porcelain triangle. Twist the two open wire-leads of the "square U" to the respective adjacent wire-leads of the triangle. The two remainine wire-leads of the "sauare U" are then bent mrvnnlieach other andtucked under 1hethi;d wire lead ofthe triangle.Thenlnst~ucrion is quite sturdy:Phe triangle supports the crucihle and the square supportsthe lid. ~~

Manhattanville College Purchase, New York 10577

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Datta V. Naik

Volume 54, Number 8, August 1977 1 497