An ounce and a half, treated in this manner, was reduced to an ounce. The process lasted three quarters of an hour.
" The substance is sent to market in this state, and is taken in powder as a tonic, or chewed with betel, with a view to renovate the con stitution." As tabasheer, says Dr. Brewster, is found only in a small number of bamboos, (arundo bambos,) we cannot regard it as a secretion from the plant in a healthy state. An intelligent native of Vizaga patam, who had inspected several hundred bam boos, observed, that in every joint which contained the tabasheer there was a small perforation evi dently made by an insect; and he conceives that the exterior juices of the plant find their way through this opening, and drying up form tabasheer. This observation, however, is by no means correct. I have found tabasheer in many joints where there was no perforation; and as the perforations are never lined with the siliceous matter, and have no accumulation of tabasheer at either end, they can have performed no part either in secreting or con veying the juices of the reed.
An examination of the joint or internode of the bamboo will probably lead us to a more satisfactory explanation. The culm or stalk of the bamboo represented by MN, Fig. 1, consists of a number of concentric rings. The outer rings, AC, BH, shown in section, are continued through the length of the reed, notwithstanding the little annular protuberance which marks externally the place of the internode AB. The inner rings, DE, GF, however, the innermost of which is a delicate membrane, do not pass onwards, but are inter rupted by the internode, and turning round at EF, they form the roof of the cavity DEFG, joining the simi lar membrane on the side FG. Be tween AE and FB, where the con centric rings diverge, the space left between them is filled up with a soft spongy mass, which forms the sub stance of the internode AB. As the sap ascends between AC and ED, it must be stopped partially at the internode between A and E, part of it passing A, and part of it being either absorbed by the spongy mass between AE, and remaining there, or passing through it to the opposite side of the stem.
But, however this may be, the juices of the plant arc collected at the internode, and could not possi bly penetrate into the inner tube while the inner ring and membrane are sound, as in the healthy plant. When this membrane, however, is destroy ed or rent by disease, or when the whole internode is in a state of mal-conformation, as I have found it, the juice or milk at the joints is immediately extra lines the roof FIE, or the bottom DG of the inner tube, and forms tabasheer by its subsequent induration.
The quantity of tabasheer, therefore, does not de pend on the size of the reed, but upon the diseased state of its joints; and the greatest quantity was found in one where the internode is completely dis organized. Captain Playfair has mentioned four or five grains as the usual quantity. In the bamboo now alluded to the quantity is fully twenty grains.
By the cutting down and transporting of the bam boo, the tabasheer encrusted upon the roof or bot tom of the cavity is detached, and is always found in separate pieces of different sizes. Its existence in any individual bamboo may therefore be known by the rattling noise which takes place by shaking the reed. A portion of it, however, often adheres to the place of its formation, and we may sometimes detect it in the pores of the spongy mass from which it has exuded. The largest piece of taba sheer are generally impressed with the inner membrane of the reed upon which it has been formed.
In opening different bamboos, the included taba sheer presents various appearances. \Vhen the tube has been perforated with holes, it has a brown dirty aspect, arising no doubt from the admission of dust; and the perforating insects are often found among the fragments. \Vhen there are no perfo rations, the tabasheer is clean and pure, presenting a great variety of aspects, depending probably on the nature of the juices, on the manner in which they have been extravasated, and on the time in which their induration has been effected. The dif ferent varieties of tabasheer may be thus enume rated.