Having: four own pestle and mortar, make it according to the instructions given (2165), which are excellent. Let a quantity be made at one time for the "Family Circle." The cayenne of commerce is adulterated with brick-dust, red wood dust, cochineal, vermilion, and red-lead. The latter two are highly injurious, and the former ones not very salutary. As to the means of detecting these, it would be a great waste of time to find them out, since all cayenne is largely adulterated. Therefore, make your own - or don't use any.