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Boats can be construc ted from glass tubing of the size desired.They are joined together,rather loosely by platinum wire, sothat all stand upright on the table while being filled-0.5 to0.75 inch of wire should be allowed between each boa t. Samplesare weighed and transferred q uantit ativel y to the desired boat . Aborosilicate glass weight is attached to the lowest boat to over-come the initial buoyancy effect or instead, the lowest boat canbe weighted.

After the head has been attached t o the proper round-glassjoint a t the to p of t he reaction cell, the glass fiber tare ad is un-wound until the series of boats may be attac hed to it. Th ethread is then rewound, and the samples are stored in the upperpart of the cell until needed.

A N A L Y T I C A L C H E M I S T R Y

The samples should be kept sufficiently high in th e system soth at solvent does not condense on them. The time required forcomplete solution depends on the solubility of t he sa lt and t hedegree of stirr ing. Soluble salts such as ammonium ni trate can bedissolved completely and evenly in liquid ammonia within a fewminutes.

Samples of extremely small size may be prepared by addingmeasured volumes of dilute solutions of t he sal ts to t he boats .The solvent can be carefully removed by drying or evacuating,thus leaving the desired amou nt of material in the boat.

This method of additi on is limited to nonhygroscopic solutesIn this laboratory it has been applied to liquid ammonia systems,but it should be equally applicable t o other systems.

Stability Tube with Foam Breaker. Gordon S. Fisher (presentaddress, Naval Stores Stat ion, Bureauof Agricultural and Indus-trial Chemistry, Olustee, Fla.) and Nelle J . Morris, SouthernRegional Research Laboratory, Xew Orleans 19, La.

U R I N G an investigation of the keeping quality of peanut but-D ter, crude oils extracted from this produc t and from raw androasted peanuts were subjected to the active oxygen method forthe determination ofthe stability of fatsand oils 1 , 4 . Inthis method 20-gram

samples of oil a reaerated at 97.7 C.in 25 X 200 mm.tu be s. When themethod was appliedto crude oils ex-tracted from peanutbutter and peanuts,foaming occurred tosuch an extent thatmost of the oil wascarried out of thetube with the airs t r e a m b e f o r e th edetermination couldbe completed.

Neither use of thea i r-o u t l e t tube de-s c r i b e d b y K i n g ,Roschen, and Irwin

2 ) nor use of theaerat ion tube de-scribed by Riemen-schneider, Turer, an dSpeck 8) vercamethe difficulty. Inorder t o control ex-cessive foaming, anall- gl aes stability

B 5 mm.

Figure 1. Stability Tube withFoam Breaker

AB . Foam breakerC. 1-mm. openingD Bulb approximately 60 m m . in

lengthE . Tube approximately 20 mm. in

length with tip drawn to I-mm.opening

F Tube below bulb approximately 90m m . in length and extending atleast 3 mm. below bottom of G

G A i r inlet tube

25 X 200 mm. sample tube

tube was developed and has been used for approximately 2 yearswith satisfactory results.

The stability tube with foam breaker illustrated in Figure 1comprises a 25 X 200 mm. sample tube attached to the innerpart of a 29/42 standa rd-tap er joint, and an aeration and de-foaming device attac hed to the outer part of the joint. Thefoam breaker is the outlet tube. Air leaving the apparatuspasses through t he 1-mm. opening, C in the foam breaker.

Any foam th at is produced as a result of aeration is forcedthrough the 1-mm. opening into the relatively large bulb, Dwhere the bubbles collapse and permit the oil to drain back intothe sample tube.

LITER 4TURE CITED

(1) A M E R I C A N HEMICAL OCIETY, ommittee on Analysis of Com-mercial Fats and Oils IND. NG. CHEM., NAL.ED., 17 336-40 1945).

2 ) King, A E., Roschen. H. L. arid I r w i n IT. H., Oil S o a p , 10,105-9 1933).

3) Riemenschneider, R. I -., urw, J . . and Speck R. M . Ihzd. . 20

4) \\-heeler, D . H., I b i d . , 9 S9-07 11932).169-71 1943).

Simple Flask for Titrations under an Inert Atmosphere. J . L.Myers and Percy Fainer, Chemistry Wing, Canadian hrma-ment Research and Development Establishment,Quebec,Canada

HIS flask was developed primarily for carrying out titrationsT with titanous chloride. It s main advanta ge is the eliminationof the cumbersome lengths of rubber tubing normally used t oconnert the titration flask n-ith the source of carbon dioxide.

' o GROUND G L A S S JOINT

3 RUBBER STOPPER

T E S T T U B E

2 3 m m 1 4 0 m m

It has proved particularly useful when the procedure requires th eflask to be moved from one location to another, as, for example,

when it is necessary to reflux a solution and then cool it in thesink before titration is carried out. It should prove useful alsoin any titration or reaction conducted under an inert atmosphereof carbon dioxide.

The flask is easily constructed by sealing a test tube onto aflask fitted with an inte rnal delivery tu be. The size of t he flaekand test tube depend on the work at hand,

Several flasks of this design have been in use in the aut hors'laboratory for over a year. Contra ry to first opinion, they havebeen found easy to handle, very stable, and not subject toheavy breakage. Enough dry ice can be pu t in a 23 X 140 mm.test tube to last about 40 minutes. This includes a 15-minutereflux period during which the dry ice is in close proximity to ahot plate.