RES 



RET 



some dozen diflerent plants with red- 

 dish-coloured roots. 



RED SPIDER, PLANT MITE. 

 Acanus ii:larius. A small red insect 

 which spins a uel, and lives on ihe 

 juices of many plants and trees, at- 

 taching itself to the lower side of the 

 leaf It is especially injurious to hot- 

 houses. They are destroyed hy fre- 

 quent syringing with cold water, hy 

 fumigations and washes of whale-oil 

 soap and water. 



RED TOP. A name sometimes 

 given to herd's grass, and also to a dry 

 perennial grass of the Middle States 

 (Tricuspis) of little or no value. 



RED WATER. A disease ofoat- 

 tle. See Ox. 



RED WORM. An old name for 

 the wire-worm. 



REED. The gew^ Amndo, tall, 

 aquatic, and bogey grasses. They 

 may be destroyed by draining the 

 soil, by limin? <ind ashes. The soil 

 is usually vr.'y fertile. 



REED i-TR.A.SS. Canary grass. 

 REFLECTION. The throwing 

 back jf the rays of heat or light by a 

 po'ished surface or mirror. 



REFLEXED. Bent back, turned 

 back. 



REFRACTION. The action ex- 

 erted by water, glass, and all trans- 

 parent bodies of changing the direc- 

 tion of rays of light, so as to make 

 them appear bent. 



RE.MIGES. The quill feathers of 

 birds. 



REMIPES. An order of coleop- 

 terous insects which are capable of 

 swimming. 



REMITTENT FEVERS. Fevers 

 which are subject to periodical par- 

 oxysms, as the ague, bilious fever, &.c. 

 ilENAL. Relating to the kidnevs. 

 RENTFORM. Kidney-shaped," of 

 the shape of a kidney bean. 

 RENNET. See Cheese. 

 REPENT. Running on the 

 ground. 



REPTILIA. Cold-blooded verte- 

 brate animals, as snakes, tortoises, 

 fro2s, lizards, &,c. 



RESIN. An inflammable product 

 of the vegetable kmgdoui, rich in car- 

 bon and hydrogen, soluble in alcohol, 



but insoluble in water. There are a 

 great number of species, some of 

 whi(di are evidently oxidyzed oils. 

 They are used in varnishes. 



RFSERVOIR. A tank or artificial 

 excavation to hold water. 



RESOLUTION. In farriery, the 

 discussion or dispersion of inflamma- 

 tory gatherings or abscesses, hy ap- 

 plying leeches and other means. 



]{ E S P I R A T ION. The act of 

 breathing. It is accomplished by the 

 movements of the diaphragm and 

 muscles of the chest. Atmospheric 

 air passing into the lungs is changed, 

 oxygen being separated from it and 

 absorbed into the blood, and four per 

 cent, of carbonic acid thrown out. 

 Water also passes off from the lungs. 

 By these changes heat is produced. 

 The effect of respiration is to alter 

 the colour of the blood from black to 

 bright red ; it is at the commence- 

 ment of life, and any interruption of 

 the function is rapidiv fatal. 



REST HARROW. Ononis, a 

 prickly shrub. 



RETE MUCOSUM. The part of 

 the skin immediately below the scarf- 

 skin (epidermis). 



RETIARIES. Spiders which spin 

 webs. 



RETICULATE. Like a net. 

 RETICULU.M. The honey-comb 

 bag of ruminants. See Ox. 



RETINA. The nervous layer at 

 the back of the eye which receives 

 the images of things. 



RETORT. A chemical vessel em- 

 ployed in a variety of distillations. 

 It is generally made of glass or earth- 

 en-ware, and sometimes is provided 

 with a stopper so placed above the bulb 

 as to enable substances to be intro- 

 duced into it without soiling the neck-; 

 in this case it is called a tubulated 

 retort. A receiver is usually annexed 

 to it for the purpose of collecting the 

 products of distillation. Fig. 1 rep- 

 Fig. 1. 



659 



