SPICES AND CONDIMENTS. 197 



ADC! if y is the per cent, of residue, a the per cent, in pure pepper, b the 

 per cent, in olive stones, the amount of addition can be calculated from 

 the following equations: 



p-a 



y= - 



1) a 



where b can be replaced by 74.5 or 65.5 as the case may be. 



Working in this way 10 ground peppers, guaranteed pure, were found 

 to contain from 40 to GO per cent, of olive stones, and these contained 

 "P. I)." to the extent of 14 to 20 per cent, 



Control experiments with known mixtures seem to have been satis- 

 factory. 



The same author also extended his experiments to a comparison of 

 the properties and separation of the cellulose derived from a mixture of 

 pepper and olive stones, depending upon the difference in specific 

 gravity, with re3ults which can be found in his original paper. 



The residues of starch factories always contain enough starch grains 

 to make their identification easy. 



Very recently Chas. Heisch* has given in the Analyst his experience 

 in the examination of peppers, to see if there were any reliable mode 

 of judging of the amount of adulterants in adulterated samples except 

 by determinations of ash which give no indication of added organic 

 matter. He also endeavored to find if it were possible to cleanse pep- 

 per corns so that the ash should be free from sand. Assisted by a 

 large buyer and grinders of pepper he found that as the result of the 

 grinder's experience no ground pepper should be sent to market which 

 contains over G per cent, of total adi. In this respect they agree with 

 the Bavarian chemists. He also placed some faith in the determina- 

 tion of starch and calculated, as did Lenz, his results on dry ash free 

 organic matter. 



The starch was estimated u by boiling tho finely ground pepper for 

 three hours with 10 per cent, hydrochloric acid, and taking the rotation 

 in the resulting liquid." He endeavored to check his results by deter. 

 mining that there was insufficient " gum or other matters to affect the 

 rotatory power" but neglects to see how much of the substances allied 

 to cellulose are converted into optically active substances which would 

 probably be important. Stating the results, however, as reducing sugar 

 equivalent to pepper with Lenz, the error becomes of slight importance. 



The determination of piperine was rough, and the results seemed of 

 i little service. 



"Aualyst, 2, 180-190, October, 1880. 



