150 plint's natukal history. [Book XII. 



the second rank in estimation, the bark the third, and the 

 wood being the least esteemed of all. Of the wood, that kind 

 which resembles boxwood is considered the best : it has also 

 the strongest smell. The best seed is that which is the largest 

 in size and the heaviest in weight ; it has a biting or rather 

 burning taste in the mouth. Balsamum is adulterated with 

 hypericin 78 ' from Petra, but the fraud is easily detected, from 

 the fact that the grains of the latter are larger, comparatively 

 empty, and longer than those of balsamum ; they are destitute 

 also of any pungency of smell, and have a flavour like that 



of pepper. . 



As to the tears of balsamum, the test of their goodness is 

 their being unctuous to the touch, small, of a somewhat reddish 

 colour, and odoriferous when subjected to friction. That of 

 second-rate quality is white ; the green and coarse is inferior, 

 and the black is the worst of all ; for, like olive-oil, it is apt 

 to turn rancid when old. Of all the incisions, the produce is 

 considered the best of those from which the liquid has flowed 

 before the formation of the seed. In addition to what has 

 been already stated, it is often adulterated with the juice of 

 the seed, and it is with considerable difficulty that the fraud is 

 detected by a slight bitterness in the taste, which ought to be 

 delicate and without the slightest mixture of acidity, the only 

 pungency being that of the smell. It is adulterated also with 

 oil of roses, of Cyprus, of mastich, of balanus, of turpentine, 

 and of myrtle, as also with resin, galbanum, and Cyprian wax, 

 just as occasion may serve. But the very worst adulteration 

 of all, is that which is effected with gum, a substance which 

 is dry when emptied into the hand, and falls to the bottom 

 when placed in water ; both of which are characteristics of the 

 genuine commodity. Balsamum, in a genuine state, should be 

 quite hard, but when it is mixed with gum a brittle pellicle 

 forms upon it. The fraud can also be detected by the taste, 

 aud when placed upon hot coals it may easily be seen if there 

 has been any adulteration with wax and resin ; the flame too, m 

 this case, burns with a blacker smoke than when the balsamum 

 is pure "When mixed with honey its qualities are imme- 

 diately changed, for it will attract flies even in the hand. In 

 addition to these various tests, a drop of pure balsamum, if 

 placed in luke-warm water will settle to the bottom of the 

 78* See 13. xxvi. cc. 53, 54. 



