468
CHARLES S. R O Y E R .
/:lca?@k. ,Wt~fhod’1;~. 2 .--Same
data as before. Molecular weight.
Molecu!ar weight
Atiiuunt SalICO,
CO,>: per cent. CO, found = KaHCO, : x . -. 44 : Ly.c)s 84 :47.3255*
97.7 I -9 7 . 3 2 55 = 0.3845
Molecular weight) : (Difference) NaHCO, found Molecular weight Per cent. Na,CO, = Na?CO, .X 2 i : 0.3845= 106 : 1.852. I\;a,CO, = I .8 j 2 per cent. X a H C O 3 = 9 j . 8 j 8 per cent. Proof: I , 8 5 2 X 0.4150943 = 0.76875 95.858 x 0.523809j = 5 0 . 2 1 133 Molecular weight
)-(
(
jo .gSooS ~~
ACCURACY O F THE DYEING TEST. BY C r f A X L E S S . B O Y E R . I f l > E S . K.J . ,
April, 6 , 19j.
ABSORBENT BLOCKS.1 'r. AUSTEN A N D W. H O M E R BROADHURST.
B Y PETER
K e c e l v r d April r6. ,895.
F
OR drying moist precipitates unglazed plates are generally
used in the laboratory, but they have the disadvantages of being rather expensive, as well as fragile, while their absorptive capacity is not great. We have found that a mixture of equal parts of infusorial earth and plaster of Paris, when moistened, will set, forming a block that after drying has a very strong absorbent power for liquids. T h e plaster and infusorial earth are thoroughly mixed, then moistened with sufficient water to work easily, and placed in the molds. After setting, the blocks are placed in an air-chamber and heated for a day or two at 100°-1200 to free them from hygroscopic moisture. The molds are easily made i n the following way: A sheet of glass, the larger the better, is laid on a table, and rubbed with waste oiled with a few drops of light lubricating oil. Long glass strips, an inch wide, and one-quarter of an inch or more thick, are laid on edge on the plate at a distance apart of six inches, if the block is intended to be of that size, and cross-pieces of the sanie kind of glass strips, but cut irLsuitable lengths, are placed between the long parallel strips, thus rnaking squares. T h e strips should also be oiled a little. T h e wet mixture is poured in and the top smoothed with a straight edge of wood. After setting, the strips of glass are easily removed and the blocks come off the plate easily, and are ready to be placed in the drying oven. T h e surface next to the glass plate is very smooth. 1Kead before t h e K. Y . Section, March R. 1895
