EGG 



EHR 



become visible, and are seen ascending in 

 form of smoke ; constituting what, in 

 animals and plants, makes the matter of 

 perspiration. 



Nothing can exceed the suhtility of the 

 odoriferous effluvia of plants and other 

 bodies. Mr. Boyle tells us, that having 

 exposed to the open air a certain quantity 

 of asafoetida, he found its weight di- 

 minished only the eighth part of a grain 

 in six days : hence if we suppose, that 

 during all that time a man could smell 

 the asafoetida at the distance of five feet, 

 it will appear that its effluvia cannot ex- 



ceedthe JwitVwIwmOTVf P art of an 

 inch in magnitude 



The effluvia of mineral substances are 

 called steams ; and when collected in 

 mines, or other close places, damps. See 

 GAS. 



Malignant effluvia are assigned by phy- 

 sicians as the cause of the plague, and 

 other contagious diseases ; as the jail-dis- 

 temper, hospital-fever, and the like. 



EFT. See LACERTA. 



EGGS. The eggs of hens and of birds, 

 in general, are composed of several dis- 

 tinct substances. 1. The shell or exter- 

 nal coating, which is composed of car- 

 bonate of lime .72, phosphate of lime .2, 

 gelatine .3; the remaining .23 are, per- 

 haps, water. 2. A thin, white, and strong 

 membrane, possessing the usual charac- 

 ters of animal substances. 3. The white 

 of the egg, for which see ALBUMEN. 4. 

 The yolk, which appears to consist of an 

 oil of the nature of fat oils, united with a 

 portion of serous matter sufficient to ren- 

 der it diffusible in cold water, in the form 

 of an emulsion, and concrescible by heat. 

 Yolk of egg is used as the medium for 

 rendering resins and oils diffusible in wa- 

 ter. An oil of eggs is procured by ex- 

 pression from the yolks of eggs, previous- 

 ly roasted, to deprive the serous part of 

 its fluidity. A slight empyreuma is given 

 to the oil by this treatment, which might 

 probably be avoided by applying no great- 

 er heat than, on trial, might be found suf- 

 ficient to coagulate the serum. 



The products afforded by the several 

 parts of eggs subjected to destructive dis- 

 tillation, are nearly the same as are ob- 

 tained by that method from other animal 

 matters. 



Mr. Reaumur found that eggs might be 

 preserved during months or years by be- 

 ing covered with mutton-suet, or any 

 other fat substance. And Mr. Parmentier 

 observed that eggs of hens that have had 

 no connection with a cock kept much 

 belter than those which are fecundated : 



he adds too, that they are not inferior in 

 size or flavour, and that the hens lay quite 

 as many ; so that those who keep fowls 

 for the sake of eggs alone should have 

 hens only, without any cocks. He re- 

 commends the common hen as the most 

 productive, and the black legged as su- 

 perior to the yellow. 



EGYPTIANS, or Gypsies, a wandering 

 tribe of people, whose origin is very ob- 

 scure ; they inhabit different countries of 

 Europe, and are every where remarkable 

 as thieves, fortune tellers, &c. By the laws 

 of England gipsies were formerly subject 

 to imprisonment and forfeiture of goods, 

 but they art now considered chiefly as 

 rogues and vagabonds, and are describ- 

 ed as such in .the vagrant act. 4 Black. 

 166. 



EHRETIA, in botany, a genus of the 

 Pentandria Monogynia class and order. 

 Natural order of Asperifoliae, Borragineae, 

 Jussieu. Essential character : berry two- 

 celled ; seeds solitary, two-celled ; stigma 

 emarginate. There are five species. These 

 are trees or shrubs ; the leaves in some 

 are smooth, in others scabrous ; the flow- 

 ers in panicles, terminating, and axillary. 

 E. tinifolia, Tinus-leaved Ehretia, is an 

 upright tree, from twenty to thirty feet 

 in height, with an oblong thick head ; 

 branches unarmed, roundish, subdivid- 

 ed ; leaves alternate, veined, about four 

 inches long, on short petioles ; calyx five- 

 parted, with minute, ovate, segments ; 

 corolla a little larger than the calyx, with 

 acute segments finally rolled back : fila- 

 ments longer than the corolla; style 

 scarcely shorter than the stamens, oval- 

 shaped, bifid ; stigmas simple ; berry 

 spherical. This plant is a native of Cuba 

 and Jamaica ; flowering in February. 



EHRHARTA, in botany, a genus of 

 the Hexandria Monogynia class and or- 

 der. Essential character : calyx a two- 

 valved, one-flowered glume ; corolla dou- 

 ble, each two-valved ; the outer com- 

 pressed. There are five species, of which 

 E. cartilaginea is a very beautiful smooth 

 grass ; it has a perennial fibrous root ; 

 culms erect, jointed about two feet high ; 

 leaves sheathing, the lower ones a hand 

 in length, the upper ones much shorter ; 

 disk smooth ; edge cartilaginous and cre- 

 nate ; panicle oblong, consisting of fifteen 

 or twenty flowers j peduncles capillary, 

 loose, flexuose, in threes, pairs, or soli- 

 tary, simple, or sometimes a little branch- 

 ed, growing thicker at the top ; nectary 

 and filaments white ; anthers yellow. This 

 plant was first observed at the Cape by 

 Thunberg. 



