12 
ESSAY ON SCAMMONT. 
light ash colour, as if rubbed on one surface ; dark slate, 
slightly polished on the other. It breaks with a short frac- 
ture, presenting a pretty uniform surface, darker towards the 
edge or outer portion, and uniformly light slate coloured in 
the centre. Its structure is homogeneous and dense, with 
few and very minute elongated pores. A few white points 
are perceptible on minute examination, and here and there 
exceedingly minute shining particles. It breaks down like 
starch that has been wet and dried, affording a uniform ash 
powder. It has a rancid cheese-like odour, and a nauseous 
rancid, somewhat bitter taste. It contains 
Resin, .... 22. 
Aq. ext. . . . 7.00 
Earthy matter, . . 2.50 
Veg. mat., destructible, . 60.00 
Loss and water, . . 8,50 
100.00 
It produces a deep blue with iodine, and effervesces with 
muriatic acid. This specimen was derived from New York. 
Gummy Scammony, 
In cakes or masses doubly convex, six inches wide and 
one and a half inches thick, polished and dark brown ex- 
ternally, internally greyish brown,hard,horny, homogeneous, 
with great difficulty broken, fracture rough, edge of fracture 
semi-transparent, odour decided, somewhat gritty to the 
teeth, gummy to the taste, rendering the saliva viscid but 
not opaque, shining and sticky when moistened; when rub- 
bed with the finger giving a tenacious mucilage, dirty but 
not milky; powder dirty gray ; with great difficulty reduced 
to powder. It contains 
Resin, ... . . 13.00 
Aq. ext. . . . 35.00 grs. 
Earthy matter, . , 10.00 
Veg. matter, destructible, . 37.50 
Loss, .... 4.50 
100.00 
