APPENDIX.

I. ANALYTICAL NOTES AND EXPERIMENTS.

1. ACTION OF WATER UPON GLASS AND PORCELAIN VESSELS, IN THE PROCESS OF EVAPORATION (to § 41).

A large bottle was filled with water cautiously distilled from a copper steam apparatus with a tin condensing tube. All the experiments in 1 were made with this water.

a. 300 c.c., cautiously evaporated in a platinum dish, left a residue weighing, after ignition, 0·0005 grm. = 0·0017 per 1000.

b. 600 c.c. were evaporated, boiling, nearly to dryness, in a wide flask of Bohemian glass; the residue was transferred to a platinum dish, and the flask rinsed with 100 c.c. of distilled water, which was added to the residue in the dish, the fluid in the latter was then evaporated to dryness and the residue ignited.

After ignition, the residue weighed .
Deducting from this the quantity of fixed matter
originally contained in the distilled water, viz.

There remains substance dissolved out of the glass. = 0.0153 per 1000.

0.0104 grm.

In three other experiments, made in the same manner, 300 c.c. left, in two 0.0049 grm., in the third 0.0037 grm.; which, calculated for 600 c.c., gives an average of

And after a deduction of

= 0.013 per 1000.

0.0090 grm.

0.0012

We may therefore assume that 1 litre of water dissolves, upon protracted boiling in glass vessels, about 14 milligrammes of the constituents of the glass.

c. 600 c.c. were evaporated nearly to dryness in a dish of Berlin porcelain, and in all other respects treated as in b

The residue weighed

Deducting from this the quantity of fixed matter contained in the distilled water, viz. .

0.0015 grm.

2. ACTION OF HYDROCHLORIC ACID UPON GLASS AND PORCELAIN VESSELS, IN THE PROCESS OF EVAPORATION (to § 41).

The distilled water used in 1 was mixed with of pure hydrochloric acid.

a. 300 grms., evaporated in a platinum dish, left 0·002 grm. residue. b. 300 grammes, evaporated first in Bohemian glass nearly to dryness, then in a platinum dish, left 0.0019 residue; the dilute hydrochloric acid, therefore, had not affected the glass.

c. 300 grammes, evaporated in Berlin porcelain, &c., left 0·0036 grm., accordingly, after deducting 0.002, 0·0016 0.0053 per 1000.

=

d. In a second experiment made in the same manner as in c., the residue amounted to 0·0034, accordingly, after deducting 0-002, 0·0014= 0.0047 per 1000.

Hydrochloric acid, therefore, affects glass much less than water, whilst porcelain is about equally affected by water and dilute hydrochloric acid. This shows that the action of water upon glass causes the formation of soluble basic silicates.

3. ACTION OF SOLUTION OF CHLORIDE OF AMMONIUM UPON GLASS AND PORCELAIN VESSELS, IN THE PROCESS OF EVAPORATION (to § 41).

In the distilled water of 1, of chloride of ammonium was dissolved, and the solution filtered.

a. 300 c.c., evaporated in a platinum dish, left 0-006 grm. of fixed residue.

b. 300 c.c., evaporated first nearly to dryness in Bohemian glass, then to dryness in a platinum dish, left 0.0179 grm. ; deducting from this 0-006 grm., there remains substance dissolved out of the glass, 0·0119 = 0.0397 per 1000.

c. 300 c.c., treated in the same manner in Berlin porcelain, left 0·0178; deducting from this 0.006, there remains 0·0118 = 0.0393 per 1000.

Solution of chloride of ammonium, therefore, strongly affects both glass and porcelain in the process of evaporation.

4. ACTION OF SOLUTION OF CARBONATE OF SODA UPON GLASS AND PORCELAIN VESSELS (to § 41).

In the distilled water of 1, of pure crystallized carbonate of soda was dissolved.

a. 300 c.c., supersaturated with hydrochloric acid and evaporated to dryness in a platinum dish, &c., left 0·0026 grm. of silicic acid = 0·0087 per 1000.

b. 300 c.c. were gently boiled for three hours in a glass vessel, the evaporating water being replaced from time to time; the tolerably concentrated liquid was then treated as in a; it left a residue weighing 0.1376 grm.; deducting from this the 0·0026 grm. left in a, there remains 0.135 grm. = 0·450 per 1000.

c. 300 c.c., treated in the same manner as in b, in a porcelain vessel, left 0.0099; deducting from this 0.0026 grm., there remains 0·0073 = 0.0243 per 1000.

Which shows that boiling solution of carbonate of soda affects glass very strongly, and porcelain also in a very marked manner.

5. WATER DISTILLED FROM GLASS VESSELS (to § 56, 1).

42.41 grammes of water distilled with extreme caution from a tall

glass flask with a Liebig's condenser, left, upon evaporation in a platinum dish, a residue weighing, after ignition, 0·0018 grm., consequently 23361

6. SULPHATE OF POTASSA AND ALCOHOL (to § 68 a).

a. Ignited pure sulphate of potassa was digested cold with absolute alcohol, for several days, with frequent shaking of the mixture; the fluid was filtered off, the filtrate diluted with water, and then mixed with chloride of barium. It remained perfectly clear upon the addition of this re-agent, but after the lapse of a considerable time it began to exhibit a slight opalescence. Upon evaporation to dryness, there remained a very trifling residue, which gave, however, distinct indications of the presence of sulphuric acid.

b. The same salt treated in the same manner, with addition of some pure concentrated sulphuric acid, gave a filtrate which, upon evaporation in a platinum dish, left a clearly perceptible fixed residue of sulphate of potassa.

7. DEPORTMENT OF CHLORIDE OF POTASSIUM IN THE AIR AND AT A HIGH TEMPERATURE (to § 68, c.)

0-9727 grm. of ignited (not fused) pure chloride of potassium, heated for 10 minutes to dull redness in an open platinum dish, lost 0-0007 grm.; the salt was then kept for 10 minutes longer at the same temperature, when no further diminution of weight was observed. Heated to bright redness and semi-fusion, the salt suffered a further loss of weight to the extent of 0.0009 grm. Ignited intensely and to perfect fusion, it lost 0.0034 grm., in addition to the former 0.0007 and 0·0009 grm.

Eighteen hours' exposure to the air produced not the slightest increase of weight.

8. SOLUBILITY OF POTASSIO-BICHLORIDE OF PLATINUM (BICHLORIDE OF PLATINUM AND CHLORIDE OF POTASSIUM) IN ALCOHOL (to § 68, d).

a. In absence of free Hydrochloric Acid.

a. An excess of perfectly pure, recently precipitated potassio-bichloride of platinum was digested for 6 days at from 59° to 68° F., with alcohol of 97.5 per cent., in a stoppered bottle, with frequent shaking of the mixture. 72.5 grammes of the perfectly colorless filtrate left upon evaporation in a platinum dish, a residue which, dried at 212° F., weighed 0·006 grm. The solution of 1 part of potassio-bichloride of platinum requires therefore 12,083 parts of alcohol of 97.5 per cent.

B. The same experiment was made with spirit of wine of 76 per cent. The filtrate was nearly colorless; upon evaporation, slight blackening ensued, on which account the residue was determined as platinum. 75.5 grammes yielded 0·008 grm. of platinum, corresponding to 0-02 grm. of the potassio-bichloride. One part of the latter salt dissolves accordingly in 3,775 parts of spirit of wine of 76 per cent.

Y. The same experiment was made with spirit of wine of 55 per cent. : the filtrate was distinctly yellowish. 63.2 grammes left 0.0241 grm. of platinum, corresponding to 0.06 grm. of the potassio-bichloride. One part of this latter salt dissolves accordingly in 1,053 parts of spirit of wine of 55 per cent.

b. In presence of free Hydrochloric Acid.

Recently precipitated potassio-bichloride of platinum was digested cold

with spirit of wine of 76 per cent., to which some hydrochloric acid had been added. The solution was yellowish; 67 grammes left 00146 grm. of platinum, which corresponds to 0-0365 grm. of the potassio-bichloride. One part of the latter salt dissolves accordingly in 1,835 parts of spirit of wine of 76 per cent., mixed with hydrochloric acid.

9. SULPHATE OF SODA AND ALCOHOL (to § 69 a).

Experiments made with pure anhydrous sulphate of soda, in the manner described in 6, showed that this salt comports itself both with pure alcohol, and with alcohol containing sulphuric acid, exactly like the sulphate of potassa.

10. DEPORTMENT OF IGNITED SULPHATE OF SODA IN THE AIR (to § 69, a).

2.5169 grammes of anhydrous sulphate of soda were exposed, in a watch-glass, to the open air on a hot summer day. The first few minutes passed without any increase of weight, but after the lapse of 5 hours there was an increase of 0·0061 grm.

11. EXPERIMENTS WITH NITRATE OF SODA (to § 69, b).

a. 4.5479 grammes of pure nitrate of soda were exposed, in a state of fusion, to the air (in April, in fine weather); after the lapse of 24 hours, there was an increase of weight of 0.0006 grm.

b. 4.5479 grammes of pure nitrate of soda were dissolved in water, in a platinum dish, and pure nitric acid added to the solution; the mixture was then evaporated to dryness on the water-bath, and the residue cautiously heated until the mass at the bottom of the dish began to fuse. The contents of the dish weighed, after cooling, 4.5503 grammes. It was then again heated to complete fusion, and when cold it weighed 4.5474 grammes.

12. DEPORTMENT OF CHLORIDE OF SODIUM IN THE AIR (to § 69, c). 4-3281 grammes of chemically pure, intensely ignited (but not fused) chloride of sodium, which had been cooled under a bell-glass over sulphuric acid, acquired during 45 minutes' exposure to the (somewhat moist) air, an increase of weight of 0.0009 grm.

13. DEPORTMENt of Chloride OF SODIUM UPON IGNITION BOTH WITH AND WITHOUT CHLORIDE OF AMMONIUM (to § 69, c).

4-3281 grammes of chemically pure, ignited chloride of sodium were dissolved in water, in a moderate-sized platinum dish, and pure chloride of ammonium was added to the solution, which was then evaporated and the residue gently heated until the evolution of chloride of ammonium fumes had apparently ceased. The residue weighed 4.3334 grammes. It was then very gently ignited for about 2 minutes, and after this reweighed, when the weight was found to be 4:3314 grammes. A few minutes' ignition at a red heat reduced the weight to 4.3275 grammes, and 2 minutes' further ignition at a bright red heat (upon which occasion white fumes were seen to escape), to 4.3249 grammes.

14. DEPORTMENt of Chloride OF AMMONIUM UPON EVAPORATION AND DRYING (to § 70, a).

0.5625 gramme of pure and perfectly dry chloride of ammonium was dissolved in water, in a platinum dish, and the solution was evaporated to dryness on the water-bath; the weight was now found to be 0·5622 gramme (ratio 100 99.94). It was again heated for 15 minutes in the

water-bath, and afterwards re-weighed, when the weight was found to be 0.5612 gramme (ratio 100: 99-77). Exposed once more for 15 minutes to the same temperature, the residue weighed 0-5608 gramme (ratio 10099-69).

15. SOLUBILITY OF AMMONIO-BICHLORIDE OF PLATINUM (BICHLORIDE OF PLATINUM AND CHLORIDE OF AMMONIUM) IN ALCOHOL (to § 70, b).

a. In absence of free Hydrochloric Acid.

a. An excess of perfectly pure, recently precipitated ammonio-bichloride of platinum was digested for 6 days, at 59° 68° F., with alcohol of 97.5 per cent., in a stoppered-bottle, the action of the alcohol being aided by frequent agitation.

74.3 grammes of the perfectly colorless filtrate left, upon evaporation in a platinum dish, a residue of platinum which, after ignition, weighed 0-0012 gramme, corresponding to 0.0028 of the ammonio-bichloride. One part of the latter salt dissolves accordingly in 26,535 parts of alcohol of 97.5 per cent.

B. The same experiment was made with spirit of wine of 76 per cent. The filtrate was distinctly yellowish.

81.75 grammes left 0.0257 gramme of platinum, which corresponds to 0.0584 gramme of the ammonio-bichloride. One part of the latter salt dissolves accordingly in 1,406 parts of spirit of wine of 76 per cent.

7. The same experiment was made with spirit of wine of 55 per cent. The filtrate was distinctly yellow. Slight blackening ensued upon evaporation, and 56.5 grammes of the filtrate left 0.0364 gramme of platinum, which corresponds to 0-08272 gramme of the ammonio-bichloride. Consequently, 1 part of the latter salt dissolves in 665 parts of spirit of wine of 55 per cent.

b. In presence of Hydrochloric Acid.

The experiment described in was repeated, with this modification, that some hydrochloric acid was added to the spirit of wine. 765 grms. left 0.0501 gramme of platinum, which corresponds to 0.1139 gramme of the ammonio-bichloride. 672 parts of the acidified alcohol had therefore dissolved 1 part of ammonio-bichloride of platinum.

16. SOLUBILITY OF CARBONATE OF BARYTA IN WATER (to § 71, b).

a. In Cold Water.-Perfectly pure, recently precipitated carbonate of baryta (Ba O, CO2) was digested for 5 days with water of 60.8°-68° F., with frequent shaking of the mixture. The solution was filtered, and a portion of the filtrate tested with sulphuric acid, another portion with ammonia; the former re-agent immediately produced turbidity in the fluid, the latter only after the lapse of a considerable time. 84.82 grms. of the solution left, upon evaporation, 0·006 of Ba O, CO,. One part of that salt dissolves consequently in 14,137 parts of cold water.

b. In Hot Water.-The same carbonate of baryta being boiled for 10 minutes with pure distilled water, gave a filtrate manifesting the same re-actions as that prepared with cold water, and remaining perfectly clear upon cooling. 84-82 grammes of the hot solution left, upon evaporation, 0.0055 grm. of carbonate of baryta. One part of that salt dissolves therefore in 15,421 parts of boiling water.

17. SOLUBILITY OF CARBONATE OF BARYTA IN WATER CONTAINING AMMONIA AND CARBONATE OF AMMONIA (to § 71, 6).

A solution of chemically pure chloride of barium was mixed with am