Twigs

CfiHi 05 0 C6H4 CH20H. Colourless, bitter crystals, m.p. 20 PC soluble in water and alcohol, insoluble in chloroform. It occurs in the leaves, bark and twigs of species of willow and poplar. On oxidation with dilute nitric acid it is converted into helicin, the glucoside of salicylaldehyde, which has been made the starting point of further syntheses. Gives populin with benzoyl chloride. 

Gr. thallos, a green shoot or twig) Thallium was discovered spectroscopically in 1861 by Crookes. The element was named after the beautiful green spectral line, which identified the element. The metal was isolated both by Crookes and Lamy in 1862 about the same time. 

Cinnamomum cassia B/um (Lauraceae) is the so-caUed cassia. It is native to southeastern China and has not been grown successfuUy outside of this area. The dried bark of this evergreen tree is stripped, ground, and sold almost exclusively in China. The leaves and twigs of the tree contain the same flavor components as the bark and are steam distUled to yield the cassia oil of commerce. Infrequently, smaU amounts of bark are bundled and exported as cassia lignea but caimot compete with the other varieties as bark spice. The Chinese prefer to seU the essential oil. 

Essential oils are isolated from various plant parts, such as leaves (patchouH), fmit (mandarin), bark (cinnamon), root (ginger), grass (citroneUa), wood (amyris), heartwood (cedar), gum (myrrh oil), balsam (tolu balsam oil), berries (pimento), seeds (diU), flowers (rose), twigs and leaves (thuja oil), and buds (cloves). 

Common materials—such as textiles in the form of fibers or fabrics, foamed rubber, foamed plastics, thin sheets of plastic, paper, corrugated cardboard, combustible dusts, dry grass and twigs, and wood shavings—are all examples of materials with large sutface areas in relation to their volumes. In a well-estabhshed fire, materials with relatively small surface areas, such as chunks of coal or logs, burn readily. 

In commercial practice the crop is taken from the tree shortly before emergence of the new brood. Some of these twigs are then tied to new trees to provide future sources of lac but the rest, sticklac, is subjected to further processing. The average yield per tree is about 201b per annum, usually one crop being allowed per tree per year. 

C. A. Lamy in the preceding year 1861/2 and named after the characteristic bright green line in its fiame spectrum (Greek Qakkog, thallos, a budding shoot or twig). 

Oiii-occ iiic--, rf eiirrc)u, a tree found i Inct-nae cedar, viclds a leaf and twig oil twig oil has the following characters -... 

TTie oil has also been investigated by Pioklea.t lie obtained 0070 ent. of nil from a mL[Pg.119]

At each cliargs ot the cylinder, about J picul of leaves and twigs aod 250 catties ( = 2+ piculs) ot water are employed the water used is mostly trom ijreoeding distillates. The distillation lasts aboul two and a bait hours,... 

The yield ot one such charge, wbeu eousistiug of leaves only, is 14 to 2 taels, aod when CDUsisting ot 70 per cent, of leaves and dO per cent, ot twigs, 2 Id 3 taels of oil. Tbe oil obtainitd tniin leaves alone is in gsDcral Ihe superior oiii . 

The rsisult ol this investigation indicates that a rather large proportion of twigs seems to be required to matcriallv reduce ihe quality... 

Incidentally if may he added that ihe residue of the leaves and twigs, after having been dri s , is used as hui i ing material. The... 

The tbin twigs showed a less percentage of essential oil than the Itaives, but this po-isessed a similar sweet taste to the oil from the leaves. The specific gravity wh-s 1[Pg.128]

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