( 349 ) 
lengthening the wooden receptacle a and the glass tube d, a double 
jacket was added to Jead off the cold vapours, which in this manner 
largely screen the liquid from heat. Moreover observing-glasses were 
used to watch the liquid streaming out. 
The whole apparatus is drawn in fig. 2, whilst fig. 1 may serve 
to further elucidate it. The lengthened wooden receptacle a, the 
paper vessel b, the caoutchouc-ring ¢, the glass-tube d, the T-piece e, 
the caoutchouc-tube f and the plate carrier / were mentioned in 
§ 2 of this paper. The steel capillary tube & is now introduced into 
the T-piece through the oblique side tube w, from which it is wholly 
insulated by means of wood and caoutchouec, the horizontal side- 
tube now leading towards a safety-tube immersed in mercury. 
The supply of liquid oxygen from the oxygen-spiral in the ethylene 
boiling flask !) can be shut off by the cock *) <, by means of a long 
wooden stem; before entering the capillary tube the liquid passes 
through a small filter. The tube & ends in front of the observing- 
tubes *) 0, which are fastened by means of a copper case and sealing- 
wax to the tube d; the jet of liquid meets a jet-catcher *) p suspended 
by means of fiddle strings to d, and spreads out in a fan over this 
tube. In order to indicate the level of liquid in a, a float g with a 
stem was used, which latter ends at the level of the observing-glasses. 
The cold vapours leave a through the holes », six in number, 
and stream downwards in the annular space between a and 5 on 
one side and the jacket s;—s3; on the other side. sj is a circular 
cylinder of compressed paper, fastened to the border of a, s3 a wooden 
bottom with an oval hole, into which an oval cylinder of paper ss 
has been glued; the minor axis of this is only a little wider than b, 
but sufficient space is left along the major axis for the vapour 
to escape). The latter then rises in the space limited by the 
jacket tj...ts tj is a copper rim, joined to the case of the ob- 
serving-tubes and fitting on the glass-cylinder ts, to which it is 
fastened by means of a caoutchouc-tube and brass tightening bands. 
tz is a wooden cylinder with holes provided with flanges to admit 
the pole-pieces; a tight fit is obtained here by means of a leather 
washer, screwed on by the wooden nuts ts t is again a glass- 
cylinder and ¢; a cork stopper. In order to prevent the cold vapours 
1) Proc. 29 Dec. °94, p. 172: Comm. N°, 14, p. 17. 
2) See Communication N°. 51. Proc. 30 Sept. °99, p. 129, Comm. N°. 51, p. 9. 
3) ib. p. 130. Comm. N°. 51, p. 10. 
4) ib. p. 127, glass C. Comm. N°. 51, p. 5. 
*) See transverse section, drawn in the figure on the right hand side of «. 
