CHAPTER IV.

MAKING THISTLE FUNNELS, U-TUBES, ETC.--COMBINING THE PARTS OF COMPLICATED APPARATUS--MERCURY, AND OTHER AIR-TIGHT JOINTS--VACUUM TAPS--SAFETY TAPS--AIR-TRAPS.

Electrodes--U-Tubes--Spiral Tubes--Thistle Funnels--Closing Tubes containing Chemicals--Construction of Apparatus Consisting of Several Parts--Modes of Combining the Parts of Heavy Apparatus--Mercury Joints--Vacuum Taps--Lubricating Taps--Air-Traps, 55-69