THE ALUMNI JOURNAL. 



229 



This view, so far as relates to the para-com- 

 pound, is borne out by the fact that the nitro- 

 guaiacol of m. p. 104° obtained by the hydroly- 

 sis of the acetyl'derivative of m. p. loi to 102°, 

 gives the__same benzoyl derivative f m. p. 102 to 

 103°) on treatment with benzoyl chloride and 

 alkali in the usual way. It may be pointed out 

 that the paranitro-derivative has been prepared 

 more especially with a view to the direct syn- 

 thesis of eugenol and related compounds, since 

 the replacement of the nitro-group by halogens, 

 and subsequently by allyl, should give rise to 

 the formation of benzoyleugenol. — Proc. Chein. 

 Soc. 



ESSENCE OF RENNET.* 



BV. J. A. FORRET. 



A formula for a satisfactory essence of rennet 

 must provide for a preparation that will pass 

 through a filter within a reasonable time and 

 produce a bright filtrate — that is, an infusion 

 not of a glairy or ropy consistence ; and fur- 

 ther, a finished article that will keep bright and 

 sweet for a considerable time. The following 

 formula is the result of experiment, and pro- 

 vided the calves' stomachs are in proper condi- 

 tion, the resulting essence leaves nothing to be 

 desired. As the stomachs vary in size and 

 rennet-value, it is advisable to treat three or 

 more at a time. They should be dry and pre- 

 served with salt ; the proper article is obtainable 

 from any reliable butcher : 



For three stomachs, take of — 



Salt 15 ounces. 



Boric acid__ .„ -% ounce. 



Rectified spirit 15 ounces. 



Water 150 " 



Opeu the stomachs and retain as much of the salt as 

 ■will adhere to the inner surface, cut into small pieces, 

 and macerate lor about an hour with frequent stirring 

 or shaking, in 50 ounces of water in which five ounces of 

 salt is dissolved ; strain through muslin and repeat 

 maceration twice with same qua.itity of brine, dissolve 

 the boric acid in the mixed strained liquors, add the 

 spirit and filter. 



Without the addition of some such medium 

 as kaolin, filtration through paper is very slow, 

 and the first few ounces that pass must be 

 returned. With about an ounce of kaolin or 

 precipitated chalk difi"used through the essence, 

 and a double filter-paper supported in the fun- 

 nel by tow and moistened with water, filtration 

 is fairly rapid, and only the first two or three 

 drachms of filtrate slightly turbid. Prepared as 

 above the color of the essence is objectionable ; 

 it varies from a very pale straw tint to what is 



* Read at the meeting of the British Pharmaceutical 

 Conference. 



practically colorless. For this I have found a 

 simple remedy in merely bringing up the color 

 to a pronounced straw by the addition of a very 

 small quantity of saffron. One drachm of the 

 essence is sufficient for a pint of milk, and if 

 stored in bottles that are full and well corked, 

 a fairly firm curd will be produced by the same 

 quantity, though the rennet be ten or twelve 

 months old. By re maceration sufficient ex- 

 haustion is effected in a few hours, and this 

 seems to be the principal factor in producing a 

 preparation free from " ropiness. " 



The detection of acetanilid in some 



CLOSELY RELATED SYNTHETICAL COM- 

 POUNDS. 

 Frank X. Moerk has tested the applicability 

 of E. Hirschsohn'stest for acetanilid in phenace- 

 tine and more or less closely related compounds. 

 Hirschsohn claims that five per cent, or more 

 can readily be identified by making a saturated 

 aqueous solution, and adding to this half a vol- 

 ume of bromine water. Antifebrine decolor- 

 izes the bromine water immediately, and in a 

 few moments a crystalline precipitate appears. 

 Phenacetine, on the other hand, is stated 

 neither to decolorize the bromine nor form a 

 precipitate. Moerk finds thatlactophenine, ex- 

 algine and phenocoU likewise produce precipi- 

 tates, so that the reaction is not very charac- 

 teristic for acetanilid. Differences, however, 

 exist with regard to the solubility of the precipi- 

 tates in petroleum ether. 



The isonitrile test as applied by others gives 

 results which can be improved upon by the ad- 

 dition of potassium permanganate. Acetanilid 

 gives the characteristic isonitrile odor, pheno- 

 coU gives a faint odor but different from the 

 isonitrile, whereas the others, when pure, yield 

 tests destitute of ordor. 



"o.i gm. of methacetine, phenacetine, lacto- 

 phenine, salophenen or phenocoll hydrate are 

 boiled with 10 c. c. of water [salophen is the 

 only one not soluble in 10 c. c. boiling water); 

 then cooled quickly by immersion in cold 

 water and filtered through cotton. To 2-3 c. c. 

 of the filtrate add an equal volume of the 5 per 

 cent, solution of potassa (or soda), boil and add 

 small fragments of potassium permanganate 

 until the green color first produced gives way 

 to a violet or purple after boiling ; then add 

 two or three drops of a mixture made of chloro- 

 form 10 c. c, alcohol 10 c. c. and water of am- 

 monia 0.5 c. c. ; boil and again add some of 

 this mixture if the permanganate has not been 

 reduced completely to brown manganic hydrate; 

 after the chloroform has vaporized by stand- 

 ing a few moments, note the odor and compare 

 it, if doubtful, with that yielded by a dilute 

 acetanilid solution. In testing exalgine omit 

 the potassium permanganate." — Am. /ourn. 

 Pharnt. 68, p, 38^. 



