WIHE SAGO-PALM.

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Fig. 136.

Particles of SagoMeal.

imported in the form of a fine amylaceous powder. It is whitish, with a bufFy orreddish tint. Its odour is faint, but somewhat unpleasant and musty. Examinedby the microscope it is found to consist of oval, more or lessovate, particles; many of which appear as if truncated, sothat they are more or less mullar-shaped. Some of them re-semble in form acaoutchouc bottle cut offat the neck. Fromtheir strong lateral shading they are obviously convex. Manyof the particles are more or less broken. Most of them havean irregulär or tuberculated surface. The hilum, when per-fect, is circular; it cracks in the form of a single slit, or of across, or in a stellate manner. The surface of the particlespresents the appearance of a seriös of concentric rings or an-nuiar lines, which, however, are much less distinct than in potato starch. Theselines are indicative of the concentric layers of which oach particle is composed.3. Gramiiatetl Sago (Grana Sagu). —Of this there are two kinds, pearl sago,and common brown sago.

a. Pearl Sago (Sagu perlatum.) —This occurs in small hard grains not ex-ceeding in size that of a pin's head, inodorous, and having little taste. Theyhave a brownish or pinkish yellow tint, and are somewhat translucent. By theaid of a Solution of chloride of lime they can be bleached and rendered perfectlywhite (bleached pearl sago). 1 am inforrned that the dealers pay seven poundsper ton for the bleaching of it. Bleached pearl sago resembles some samplesof potato sago which I have mei with, and which is sold as genuine palm sago.Pearl sago swells up in cold water. Examined by the microscope, it is foundto consist of the same kind of particles as sago meal, but all ruptured, and pre-senting very indistinct traces of rings. These peculiarities.are doubtless pro-duced by the process of granulation.

ß. Common or Broten Sago (Sagu fuscum) occurs in larger grains. Thatwhich I have usually met with consists of grains about the size ofthose of pearlbarley ; but I have received from Dr. Douglas Maclagan, of Edinburgh, a sam-ple of some nearly as large as gray peas. Common sago is whitish or brown-ish white: the same grain being whitish on one part of its surface, and brown-ish on another. Examined by a microscope, the grains of common sago arefound to consist of particles like those of pulverulent sago, perhaps somewhatmore broken and less regulär in their shape.

Adulteration. —Potato sago is sometimes sold forwhite or bleached pearl sago. The fraud can be distin-guished by the microscope. The largest particles of po-tato sago are larger than those of palm sago ; moreover,the particles of potato sago are more regularly oval andovate, more distinctly ringed, smoother, and less brokenthan those of genuine sago. When their circular hilumcracks it frequently forms two slightly diverging rents(see fig. 137). I have two varieties of potato sago, one

in grains, about the size of those of pearl sago (pearl po- Particles of Potato Sago,tato sago), the other in larger sized grains, received fromProfessor Guibourt, who teils me it is made near Paris (see Potato Starch).

Commerce. —The quantity of sago on which duty was paid in 1840 was26,895 cwts. (Trade List.) It is brought from Singapore, in bags, &c. Thequantity imported into France, in 1834, was 41,312 lbs. (Planche, Journ. dePharm, xxiii. 116.)

Composition. —Sago has not been analyzed ; but its composition is prcsumedto be analogous to that of olher starchy bodies (vol. i. p. 79).

Chemical Chakacteristios —Sago possesses thecharacteristics of ordinarystarch. A cold decoction forms ablue Compound (iodide of starch) with iodine.A filtered infusion (prepared with cold distilled water,) of pulverulent sago, or

Fig. 137.

VOL. II.

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