174 On the preparation of Opium for the China market. [March, 



eight years ago, is in general largely contaminated with oil, which is 

 easily separated by dissolving the opium in water ; and I have seen, in 

 a few instances, the same fraud attempted within the Benares agency. 

 As the oil is always in a rancid condition, its presence is betrayed by 

 its odour, as well as by the glistening appearance which it communi- 

 cates to the opium. 



19. By long exposure to the heat of the sun, the texture of opi- 

 um, whatever be its spissitude, undergoes a remarkable change, 

 through the conversion of part of its gluten into a species of bird-lime. 

 Its shortness or property of exhibiting sharp edges, when cut into 

 flakes with a knife, disappears ; and it draws out into long threads . 



These two varieties of texture may almost always be recognized in 

 cakes of Behar and Benares opium respectively ; the former being ex- 

 posed to the sun, in the process of drying the cakes, and the latter 

 not. This diversity of treatment occasions a difference between the 

 hygrometric properties of the cakes of the two agencies ; the Behar 

 cakes acquiring a more speedy but less permanent hardness than the 

 Benares : whereby, though firmer in the shell towards the end of the 

 hot winds, they are more liable than the Benares to soften and lose 

 their shape during the rains. The immediate cause of this difference 

 appears on making a clean section of the shells with a sharp knife. 

 It will thus be found, that in the Benares shells, the Uwd remains 

 visibly interstratified with the petals, dark- coloured, and tenacious ; 

 while in the Behar, it is in a great measure absorbed by the petals, 

 which are apparently in intimate contact with each other, and is not 

 to be distinguished from them ; the combination being more easily ef- 

 fected by hygrometrie changes of the atmosphere than the independent 

 strata of leaf and Uwd in the Benares cakes. 



20. While, as at present, a considerable amount of inferior opium 

 is produced, not safely applicable to any other purpose than the manu- 

 facture of Uwd, its sacrifice is no great loss. But if all the opium 

 brought to the agencies were of good quality, the substitution of some 

 less expensive vegetable paste would be an important desideratum. 

 Any strong cheap mucilage or farinaceous paste, or perhaps some 

 indigenous imitation of bird-lime, would answer for the inner portion of 

 the shell ; and an exterior coating of a resinous, waxy, or oily nature, 

 impervious to water, would defend this from the moisture of the air. 



21. In cutting open a cake for examination, the above points 

 should be attended to. It should also be observed whether the exter- 

 nal and internal surfaces of the shell are smooth : the former not 

 knotty or fissured, and none of the interior leaves of the latter detach- 

 ed among the opium : there ought, also, to be no vacuities between 



