206 EXPEEIMENT STATION RECOED. 



depending upon the conversion of the starch into sugar are cumbersome. The 

 polarimetric methods seem to be the most appropriate for this purpose. 



For the solution of the starch, the author utilizes hydrochloric acid, which 

 was first pointed out by Effront A fine paste is prepared of the potatoes with 

 a beet press or chopping machine, and 8.82 gm. (for Mohr's cubic centimeters) 

 or 8.8 gm. (for metric cubic centimeters) of the paste is brought into a 100 cc. 

 flask with the aid of 25 cc. of water, and amid stirring 25 cc. of fuming 

 hydrochloric acid (specific gravity 1.188) is added. The mixture is allowed 

 to stand for about 1 hour, stirring frequently during the interval, and then 

 water is added to make 100.35 cc. This is shaken, filtered, and polarized at 

 20° C. with a Ventzke-Soleil polariscope. The reading obtained gives the per- 

 centage of starch present. 



A more rapid method consists of weighing out 9.55 gm. (Mohr's cubic centi- 

 meters) or 9.53 gm. (metric cubic centimeters) of the potato paste into a 

 beaker glass. The weighing glass is washed off with 25 cc. of water, dried 

 with a piece of filter paper, and the paper thrown into the beaker; 25 cc. of 

 fuming hydrochloric acid is then added, stirring constantly during the process. 

 This is allowed to stand for 1 hour, stirring the mass during this period, when 

 50 cc. of water is added, shaken, filtered, and polarized as before. 



The specific gravity of citrus fruit as a factor in the separation of frozen 

 fruit, R. A. Gould (Abs. in Ong. Commun. 8. Internat. Cong. Appl. Cliem. 

 [Washington and New York], 26 {1912), Sects. Vla-XIl), p. 587).— This reports 

 briefly the results of determining the floaters among 5 varieties of sound 

 oranges and 2 varieties of sound cured lemons. The fruit was floated on 

 alcoholic solutions of various strengths and specific gravities. 



" The specific gravity varies with the growing district, the variety, the size, 

 and the time of picking. The limits of variation are too great to allow of the 

 use of any method, dependent upon the specific gravity of the fruit, for the 

 accurate commercial separation of frozen from sound fruit, although any lot 

 of partly frozen fruit can be bettered by proper treatment in alcoholic solutions 

 of the proper gravity." 



Tables showing results of attempted separation by floating fruit in 160 proof 

 alcohol and subsequently putting that fruit which floats under diminished 

 pressure and refloating in the same solution are given, also tables showing 

 proximate analyses of sound and frozen oranges of various specific gravities to 

 show additional factors which influence the specific gravity of the fruit. 



Honey examination, H. Witte (Ztschr. Offentl. Chem., 18 (1912), Nos. 19, 

 pp. 362-373; 20, pp. 390-397). — A discussion as to the value of determining the 

 nonsaccharin substances, ash, acidity, saccharose, the presence of Ley's reac- 

 tion, albuminate, the precipitation according to Lund, the presence of starch 

 sirup, Fiehe's test, Auzinger's reaction, and Thoni's precipitation reaction for 

 judging honey. The complete protocol resulting from the analyses of 53 various 

 kinds of honey is given. 



Determination of sucrose in confectionery containing cooked starch and in 

 marshmallows, C. C. Roberts {A1)S. in Orig. Commun. S. Internat. Cong. Appl. 

 Chem. [Washington and Neio York], 25 (1912), Sects. I-Ve, p. 539).— After 

 pointing out the difficulties encountered in clarifying solutions of starch paste 

 confectionery and marshmallows, a method is recommended in which dilute 

 alcohol (made by diluting 400 cc. of commercial alcohol to 1.000 cc. with water) 

 is used as a solvent for the sucrose. The normal weight, 26.048 gm. of an 

 average sample of the confectionery, is treated with some of the dilute alcohol 

 until solution has taken place, transferred to a 200 cc. flask, clarified with a 

 solution of subacetate of lead (specific gravity 1.25) or alumina cream, or both, 



