stained glass.
Table— continued .
241
Specific
Gravity.
Per Cent.Under Prf.
Specific
Gravity.
Per Cent.Under Prf.
Specific
Gravity.
Per Cent.Under Prf.
Specific
Gravity.
Per Cent.Under Prf.
■9372
149
•9530
31*0
•9685
52-2
•9846
79*2
•9376
15 3
•9534
31-4
•9689
529
•9850
79-8
•9380
15*7
•9539
31*1
•9693
53-3
•9854
80-4
•9384
160
•9542
32*3
•9697
54-2
•9858
811
•9388
16*4
•9546
32-8
•9701
54-8
•9862
81*7
•9392
16-7
•9550
33-2
•9705
555
•9866
82-3
•9396
17-1
•9553
33-7
•9709
56-2
•9870
829
•9399
17-5
•9557
34-2
•9713
569
•9874
83*5
•9403
17-8
•9561
34-6
•9718
57-6
*9878
84-0
•9407
18*2
•9565
351
•9722
58*3
•9882
84*6
•9411
185
•9569
35-6
•9726
59-0
■9886
852
•9415
18-9
•9573
36-1
•9730
59-7
•9890
85*8
•9419
19 3
•9577
36-6
•9J34
60'4
•9894 .
66 3
•9422
19-7
•9580
37*1
•9738
611
•9898
86-9
•9426
20 0
•9584
37-6
•9742
61-8
•9902
87 4
•9430
20-4
•9588
38-1
•9746
62-5
•9906
88-0
•9434
20 8
•9592
386
■9750
63'2
•9910
88-5
•9437
21-2
•9596
39 1
•9754
63'9
•9914
89-1
•9441
21*6
•9599
39-6
•9758
64 6 '
•9918
89-6
•9445
21-9
•9603
40-1
■9762
653
•9922
90.2
•9448
22 2
•9607
40-6
•9766
66*0
•9926
90-7
•9452
227
•9611
41-1
•9770
66*7
•9930
91-2
•9456
23-1
•9615
41-7
•9774
67*4
•9934
91-7
•9460
23-5
•9619
42-2
•9778
680
•9938
92-3
•9464
23 9
•9623
42-8
■9782
68-7
•9942
92-8
•9468
24*3
•9627
43-3
•9786
69-4
•9946
93-3
•9172
24-7
•9631
43 9
•9790
70*1
•9950
93*8
•9476
251
•9635
44-4
•9794
70-8
•9954
94-3
•9480
25-5
•9638
45-0
•9798
71-4
•9958
94-9
•9484
25-9
•9642
45-5
■9802
72*1
•9962
95-4
•9488
26*3
•9646
46-1
•9806
72-8
•9966
95*9
•9492
26-7
•9650
46-7
‘9810
73-5
•9970
96.4
•9496
27-1
•9654
47*3
•9814
741
•9974
96-8
•9499
27-5
•9657
47-9
•9816
74-8
•9978 •
97-3
•9503
' 28*0
•9661
48*5
•9822
75-4
•9982
97-7
•9507
28-4
•9665
49-1
•9826
76-1
•9986
982
•9511
28-8
•9669
49-7
•9830
76*7
•9990
98‘7
•9515
29-2
•9674
50'3
•9834
77*3
•9993
99-1
•9519
297
•9677
51-0
•9838
78-0
•9997
91.6
•9522
' 30-1
•9681
51-6
•9842
78-6
10000
1000
•9526
30*6
STAINED GLASS . The blues of vitrified colors are all obtained from the oxide ofcobalt. Cobalt ore (sulphuret) being well roasted at a dull red heat, to dissipate allthe sulphur and arsenic, is dissolved in somewhat dilute nitric acid, and after the addi-tion of much water to the saturated solution, the oxide is precipitated by carbonate ofsoda then washed upon a filter, and dried. The powder is to be mixed with thrice itsweight of saltpetre; the mixture is to be deflagrated in a crucible, by applying a redhot cinder to it, then exposed to the heat of ignition, washed, and dried. Three partsof this oxide are to he mixed with a flux, consisting of white sand, borax, nitre, and alittle chalk, subjected to fusion for an hour, and then ground down into an enamelpowder for use. Blues of any shade or intensity may be obtained from the above, bymixing it with more or less flux.
The beautiful greenish yellow, of which color so many ornamental glass vessels havebeen lately imported from Germany, is made in Bohemia by the following process. Oreof uranium, Uran-ochre, or Uran -glimmer, in fine powder, being roasted, and dissolvedin nitric acid; the filtered solution is to be freed from any lead present m it, by thecautious addition of dilute sulphuric acid. The clear green solution is to be evapora-ted to dryness, and the mass ignited till it becomes yellow. One part of this oxide isto be mixed with 3 or more parts of a flux, consisting of 4 parts of red lead and 1 ofground flints; the whole fused together and then reduced to powder.
Chrome Green. Triturate together in a mortar equal parts of chromate of potash andflowers of sulphur: put the mixture into a crucible and fuse. Pour out the fluid mass;when cool, grind and wash well with-water to remove the sulphuret of potash and toleave the beautiful green oxide of chrome. This is to be collected upon a filter, dried,rubbed down along with thrice its weight of a flux, consisting of 4 parts of red lead and1 part of ground flints fused into a transparent glass; the whole is now to be meltedand afterward reduced to a fine powder. * _
Violet. One part of calcined black oxide of manganese, one of zanre, ten parts ofwhite glass pounded, and one of red lead, mixed, fused, and ground. Or gold purple(Cassius’s purple precipitate) with chlorsilver previously fused, with ten times itsweight of a flux, consisting of ground quartz, borax, and red lead, all melted together;or, solution of tin being dropped into a large quantity of water, solution of nitrate of