(4) A given volume of O weighs 0.25g at a pressure of 750mm; find the weight of a like volume of O at 758mm.
APPENDIX.
INDIVIDUAL APPARATUS.
Each pupil should be provided with the apparatus given below, but in cases where great economy must be exercised different pupils may, by working at different times, use the same set. The author has selected apparatus specially adapted, as to exact dimensions, quality, and cheap- ness, for performing in the best way the experiments herein described, and sets or separate pieces of this, together with other apparatus and chemicals, can be had of the L.E. Knott Apparatus Co., 14 Ashburton Place, Boston, to which firm teachers are referred for catalogs.
4 wide-mouthed bottles (horse-radish size), with corks. 1 soda-bottle. 4 pieces window-glass (3 in. sq.). 2 pieces thick glass tubing (20 in. long, 4 in. outside diam.). 1 glass stirring-rod. 1 glass funnel (2 1/2 in. wide, 60 degrees). 2 pieces glass tubing (12 in. long; 5/8 in. diam.). 1 porcelain evaporating-dish (3 in. wide). 1 asbestus paper and 1 fine wire gauze (3 in. sq.). 1 iron (or tin) plate. 1 pair forceps. 1 triangular file and 1 round file. 1 copper wire (15 in. long). 6 test-tubes, and corks to fit. 1 wooden test-tube holder. 1 flask with cork (200cc). 1 Bunsen burner (or alcohol lamp). 1 iron ring-stand. 1 piece rubber tubing (18 in. long, 3/8 in. inside diam.). 4 reagent bottles (250cc), HCl, HNO3, H2SO4, NH4OH. 1 pneumatic trough.
Wherever in this work "Bunsen burner" or "lamp" is mentioned, if gas is not to be had, an alcohol lamp may be substituted.
GENERAL APPARATUS.
The following list includes apparatus needed for occasional use:—
Metric rules (20 or 30cm long).
Scales with metric weights (1-200 g).
Metric graduates (25 or 50cc).
Filter papers.
Metric graduates (500cc).
Reagent bottles (250 and 500cc).
Mouth blowpipes.
Platinum wire and foil.
Mortars and pestles.
Test-tube racks.
Thistle-tubes.
Filter-stands.
Beakers.
Glass tubing (3/16 in., 1/4 in., and 1 in. outside).
Rubber tubing (1/8 in., and 3/8 in. inside).
Hessian crucibles.
Porcelain crucibles.
Electrolytic apparatus, including 2 or more Bunsen cells.
Ignition-tubes.
Steel glass-cutters.
Wire-cutters.
Calcium chloride tubes.
Water baths.
Thermometers.
Barometers, etc.