SUGAR, MOLASSES, CONFECTIONS, AND HONEY. 833 



the soda lye is colored and also turbid ; under the microscope the chloroform residue 

 presents a wavy appearance without the stars. For a quantitative determination the 

 results are only approximate ; instead of 25 per cent there were obtained in three 

 determinations 22.38, 23, and 23.70 per cent. 



DETECTION OP ROSIN IN BEESWAX.* 



Determination of specific gravity of wax samples, in order to detect sophistication 

 with rosin, can be rapidly made by using officinal " Liq. ainmon. caustic" (German). 

 In this pure wax floats, while that containing rosin sinks. 



DETECTION OF ROSIN IN BEESWAX, t 



Five grams of the wax are introduced into a flask with four or five times as much 

 crude nitric acid (1.32 to 1.33 specific gravity), the mixture heated to boiling and kept 

 at that temperature for a minute. Then an equal bulk of cold water is added, and 

 then ammonia till the fluid smells strongly of it. With pure wax the alkaline fluid 

 is colored only yellow, but in presence of rosin, it is deep brown. A blank with pure 

 wax should be run simultaneously. With mixures containing rosin, the action of 

 the acid is much more vigorous than with pure wax. This method is exactly the 

 same as that accredited to Donath. 



DETECTION OF ROSIN IN BEESWAX, t 



In the literature are to be found : 



(1) Method of Donath (given elsewhere). 



(2) Schmidt's method (given elsewhere). 



(3) Hager's method : Boil a sample of wax with fifteen times its volume of a mix- 

 ture of 1 part water and 2 parts 90 per cent alcohol. Allow to fully cool, decant, or 

 filter if cloudy, and mix with an equal volume of water. If rosin is present the liquid 

 becomes cloudy or milky. With alcohol of the above strength the rosiu can be en- 

 tirely extracted, while the wax and stearic acid are unaffected. 



(4) According to the results of the pharmacy commission || wax containing rosin 

 gives with soda solution a kind of emulsiou which is tolerably permanent, remaining 

 for several days. One gram wax should be heated with 10 cc water and 3 grams 

 carbonate of soda to boiling for fifteen minutes. 



(5) Sedna's method :U Three grams of wax are to be dissolved in ten to twelve times 

 as much chloroform, 200 grams lime water added and the mixture shaken. Pure wax 

 makes an emulsion, but in presence of rosin the fluid becomes yellowish brown and 

 gray -brown flocks of rosin swim on the surface. 



On a critical trial these methods gave the following results : 



(1) Sedna's method is useless. Gray-brown flocks were not obtained even when 

 working with wax containing 20 per cent of rosin. 



(2) Hager's method is right in principle, but the sentence " with this strength of 

 alcohol (1 part water to 2 parts 90 per cent alcohol = 60 per cent alcohol) rosin can 

 be extracted, while wax and stearic acid are unaffected," is erroneous, inasmuch as 

 stearic acid if present with rosin always goes into solution, at least partially. This, 

 however, does not interfere with the test, as, under the conditions given, stearic acid 

 separates on the surface while the rosin remains emulsified. Better results may be 

 obtained by using 50 per cent alcohol instead of 60, as the former has no effect on 

 stearic acid. Two per cent of rosin can be easily detected. 



(3) The best method for the detection of rosin is that of Donath as modified by 

 Schmidt. The assertion made that 1 per cent of rosin is easily detected in this way 

 is correct. 



* Chem. Ceutralblatt, 1876, 151. 



t E. Schmidt, Ber. 10, 837 ; abs. Zeit. f. a. Chem., 1878, 509, 



t H. Rottger, Chem. Zeit., 1891, 45. 



Comment. Phami. Germ., 1873, 436. 



|| Arch. Pharm., 1886, 224, 489. 



^] Sedna, Das Wachs und seine Verwendung, 14, 



