A-l-ALYTZCAL E D I T I O S
200
Vol. 2. s o . 2
A Modified Thiele Melting-Point Apparatus' Ernest Conte THE~ I A L L I S C K R O D T
C H E M I C A L ~ ~ O R K JERSEY S , C I T Y LABORATORY,
223 TO 243 W E S T S I D E A V E . , JERSEY C I T Y ,
N.J.
containing the material under test. in respect to the rner('ury bulb of the thermometer very critical. K i t h the modificcl tube the temperature variation throughout the tube is greatly reduced, thereby accomplishing tlie much desired need r ~ f:I uniform temperature bath which is so essential to c11;t:iiii dependable melting points. This laboratory lias satisfact,orily used the tLlIJ(' I'(1r boiling-point determin is, where a uniforni tint11 is also desirablc. It lias heen used for dissol1-inp ninterinl; which require considerable slialiing and arc nut affectd hy tlie introduction of air: for extraction operations, a i d for aerating liquid materials. Other applications 1nay i i i time suggest theniselves.
Device for Fastening MeltingPoint Tubes to Thermometers' H. L. Lochte
tube is held in place either by adhesion or by tying it t o the thermometer with some suitable material depending on the bath medium used. The bent tube, A-, is connected with a water p u m p ( a s p i r a t o r ) and air is drau-n through the apparatus a t
A-
U N I V E R S I T Y O F T E X A S , AuSTIS, ' I E X .
SUMBER of schemes for prel-entA ing the aggravating tendency of melting-point tubes to slip in making meltingpoint determinations have been described and are listed in handbooks and manuals. The following simple and effective plan appears not to have been d e w i b e d before. A glass rod 3 to 5 inm. in diameter is fastened to the stem of the thermometer as indicated in the figure. Even the most vigorous stirring will not cause the tube to turn loose when in the position shown in a sulfuric acid bath. If the plan is t o be used with the Thiele melting-point apparatus the rod may be fastened by wire as shown or, preferably, be passed, along with the thermometer, through a single elongated hole in the cork. 1
T
M ' B
50 42 36
100 89 76
150 138 122
200 187 168
50
50 49.9
100 99.8 99.5
150
149 5 148.8
200 199.2 198.0
T h e above readings were taken simultaneously when the temperature a t T h a d been held within 1' C. for 5 minutes. Three standard thermometers were used; one was placed a t T , a height so that the bath just covered the mercury bulb, one a t .VI, the center, and the other a t B , the bottom of t h e tube. Stem corrections were given to all these readings. It will be noticed t h a t the temperature of the bath varies considerably a t different parts of the ordinary Thiele tube. This variation makes the position of the capillary tube, 1
Received January 24, 1930.
Received December 26, 1929.
California to Utilize Surplus Natural Gas Through the efforts of the railroad commission, arrangement has been made for the utilization of approximately 500,000,000 cubic feet of surplus natural gas in Southern California for the generation of electric power by the Southern California Edison Company in its plant a t Long Beach. This gas has hitherto been blown into the air and wasted by the gas utilities, which were required to purchase in order to obtain lowest rates in the field and to care for the peak demand in cold weather, but which have had no available market. The use of this surplus gas will result in a substantial economic saving in the cost of the gas and in the cost of operation of the utilities involved. It will also make possible a saving of stored water by the hydroelectric wing of the Edison Company. This water may also be used for irrigation purposes in times of need.
