486 



ROT 



THE UNIVERSAL HERBAL; 



ROT 



its juices flow out, but a much larger quantity is retained in 

 its vessels, and cannot be expelled. Long, very long season- 

 ing after the usual method, is requisite to deprive them of 

 their vegetating powers ; and when that is affected, the 

 timber is neither so strong nor so durable as that felled in 

 the autumn or winter. Mr. Knight has Shewn, that winter- 

 felled timber is more dense than that which is cut in the 

 spring or early part of summer. He cut two Oak poles from 

 the same stool, the one in May, the other after leaf-fall ; 

 these were dried for six weeks by a fire ; he then found the 

 specific gravity of the winter-felled to be 0.679, that of the 

 summer, 0.609. Here then is a decisive proof of the superior 

 quality of winter-felled timber. At the end of autumn, the 

 tree has completed its vegetation ; the sap and peculiar 

 juices no longer exist in it as such, but are changed into 

 wood and other solid matter, and in consequence are not so 

 much disposed to decomposition, as they were when in a 

 state of fluidity ; the water is nearly gone, and the wood, as 

 if so designed by nature, is fit for cutting, being in a state of 

 suspended animation, which state, I suppose, may be pro- 

 longed by cutting off the sources of future vivification. I 

 have noticed Elm trees which were cut down in spring, 

 germinating the succeeding spring; and, on rending away 

 part of the bark, have found the sap in circulation : had 

 these trees been cut, and converted to use, I have no doubt 

 that instead of finding a branch, I should have seen a fungus. 

 From the above I draw the conclusion, that the spring is an 

 improper time to fell timber, and that its being loaded wjth 

 juices disposes it to a hasty decay. It will be objected to 

 the plan of cutting timber in the autumn and winter, theft the 

 bark will be ruined. It has been proved, that trees have 

 continued to grow and flourish when deprived of a great 

 part of that covering; it will be of no injurious consequence 

 to the tree, then, to strip it of its bark at the most convenient 

 time, and suffer the tree to remain until autumn to complete 

 its vegetation, taking care to envelope the trunk with hay or 

 straw bands, so as to defend the sap-vessels from the sun 

 and wind. But, even supposing the growth of the tree 

 should be affected by these means, yet it will be the external 

 part alone that will suffer, and that is of but trifling conse- 

 quence, as, in the conversion of timber for shipping espe- 

 cially, that part is cut away. By these means, the timber 

 may be procured free from sa'p, and the peculiar juices, to 

 which fluids the fungi owe their Origin ; for, upon analysis of 

 it, I found they yielded most of the principles of which the 

 peculiar juices are composed : therefore procure timber free 

 from those two fluids, and fungi will be prevented. At the end 

 of autumn, a small portion of water will remain in the tree, 

 and, in conveying it to the various places at which it is to be 

 used, more will necessarily be absorbed. To expel this, and 

 to season the timber, the logs should be first sided or cut 

 out into their different qualifications, and then placed in 

 sheds constructed for that purpose, of large capacity, and 

 with sides of swinging loover boards; in these must be placed 

 stoves, the funnels of which should run through the whole 

 length of the building, and be capable of raising their atmo- 

 sphere to a temperature between 98 and 100, when some of 

 the lower boards are canted to admit a current of air ; those 

 to windward should be canted below, and those to leeward 

 aloft : care must be taken that the current of air be not very 

 rapid. In a few weeks, the timber will be fit to be removed 

 to other buildings of the same construction, but without 

 stoves; and thus it may in a short time be rendered fit for use, 

 well seasoned, and of greater durability and strength than 

 that at present used. 



Rot, Red. See Drosera Rotundifolia. 



Rot, White. See Hydrocotyle Vulgaris. 



Rotala; a genus of the class Triandria, order Monogynia, 

 GENERIC .CHARACTER. Calix: perianth one-leafed, tu- 

 bular, membranaceous, three-toothed, permanent. Corolla: 

 none. Stamina: filamenta three, capillary, the length of the 

 calix; antherse roundish. Pistil: germen superior, ovate; 

 style filiform ; stigma trifid. Pericarp : capsule ovate, sub- 

 trigonal, inclosed within the calix, three-celled, three-valved. 

 Seeds: very many, roundish. ESSENTIAL CHARACTER. 

 Calix: three-toothed. Corolla : none. Capsule: three-celled, 

 many-seeded. The only known species is, 



1. Rotala Verticillaris. Leaves in fours, sometimes on 

 the branches from five to eight, sessile, linear, sharpish, even, 

 somewhat keeled, spreading; flowers in fours, one from each 

 axil of the leaves, sessile, small; stem asending, a palm high, 

 round, jointed, even. Native of the East Indies. 



Rotang. See Calamus. 



Rothia; a genus of the class Syngenesia, order Polygamia- 

 .ZEqualis. GENERIC CHARACTER. Calix: common round- 

 ed, villose-tomentose ; scales about seven, equal, linear, 

 acute. Corolla: compound imbricate, uniform; eorollets 

 hermaphrodite, numerous, equal ; proper, one-petalled, ligu- 

 late, linear, truncate, five-toothed. Stamina: filamenta five, 

 capillary, very short ; antherse cylindrical, tubular. Pistil: 

 germen ovate ; style filiform, the length of the stamina; stig- 

 mas two, reflex. Pericarp: none; calix converging. Seeds: 

 solitary; in the disk, cylindric, turbinate, striated, with a 

 capillary down, feathered below, and sessile; in the ray, cylin- 

 drical, striated, wrapped up in chaffs without any down. 

 Receptacle : flat, in the disk hairy, in the ray chaffy ; chaffs 

 in several rows, linear, channelled, erect, sharpish, tubular 

 at the base ; outer the length of the calix, inner gradually 

 shorter. Observe. This genus is very neaily allied to 

 Andryala. ESSENTIAL CHARACTER. Receptacle: in the 

 ray chaffy; in the disk villose. Calix: of many equal scales. 



Seeds : in the ray bald ; in the disk pappose. The only 



species are, 



1. Rothia Andryaloides. Stem much branched from the 

 very base ; leaves ovate-lanceolate, clasping the stem, nearly 

 entire, downy. Annual. Native of Spain. 



2. Rothia Cheiranthifolia. Stem erect, corymbose; leaves 

 finely woolly, lanceolate, sinuated, or deeply toothed. Native 

 of Spain and the south of France, flowering in May. Annual. 



3. Rothia Runcinata. Stem erect, corymbose ; leaves 

 downy; flower-stalks villose, glandular. Biennial. Native 

 of the south of Europe. 



Rottbcellia ; a genus of the class Polygamia, order Monoe- 

 cia; or of the class Triandria, order Digynia. GENERIC 

 CHARACTER. Receptacle: common elongated into the 

 jointed rachis of a cylindrical spike, the joints alternately 

 hollowed out to receive flowers of a two-fold structure; some 

 (in the calix) one-glumed, placed on a thicker tooth, her- 

 maphrodite ; others two-glumed, each inserted (alternately) 

 on either side of the former, a little lower down, and a little 

 smaller than the former, female ; (hermaphrodites?) In some 

 species only one of this sort. Hermaphrodite, one-glumed. 

 Calix : glume one-flowered, one-valved ; valve cartilaginous, 

 ovate-oblong, truncate at the base, often emarginate, striated, 

 closing the sinus of the joint, which is in place of a second valve- 

 like lid. Corolla: glume two-valved, parallel to and shorter 

 than the calicine glume ; valves lanceolate, acute, concave, 

 membranaceous, hyaline ; outer longer, inner with the edges 

 bent in ; nectary one-leafed, lanceolate, blunt, membranace- 

 ous, hyaline, longer than the germen. Stamina : filamenta three, 

 capillary ; antherse oblong, bifid at each end. Pistil: ger- 

 men oblong ; styles two, filiform ; stigmas oblong, feathered, 



