EXP 



EXP 



uon of the oceanic flying fish, see Pisces, 

 Plate IV. fig. 2. 



EXORDIUM, in rhetoric, is the pre- 

 amble or beginning, serving to prepare 

 the audience for the rest of the discourse. 

 Exordiums are of two kinds, either just 

 and formal, or vehement and abrupt. 

 The last are most suitable on occasions 

 of extraordinary joy, indignation, or the 

 like. All exordiums should be compos- 

 ed with a view to captivate the good 

 will, or attract the attention of the audi- 

 ence. The first may be done by paying 

 them some compliment : thus St. Paul, 

 " I think myself happy, king Agrippa, 

 because I shall answer for myself this 

 day before thee, touching all the things 

 whereof I am accused with the Jews, 

 especially because 1 know thee to be ex- 

 pert in aU customs and questions which 

 are among the Jews." 



The requisites in an exordium are, 1. 

 Propriety, whereby it becomes of a piece 

 with the subject, and matches it as a 

 part does a whole : in this the Greeks 

 were very defective. 2. Modesty, which 

 very much recommends the orator to the 

 favour of his audience. And, 3. Brevity, 

 not amplified or swelled with a detail of 

 circumstances. 



EXOTERIC, iand ESOTERIC, terms de- 

 noting external and internal, and applied, 

 to the double doctrine of the ancient 

 philosophers : the one was public, or ex- 

 oteric, the other secret or esoteric. The 

 first was that which they taught openly 

 to the world, the latter was confined to a 

 small number of disciples. See PERIPA- 



TKT1CS. 



EXOTIC, an appellation denoting a 

 thing to be the produce of foreign coun- 

 tries. Exotic plants of the hot climates 

 are very numerous, and require the ut- 

 most attention of the gardener to make 

 them thrive with us. 



EXPANSION, in natural philosophy, 

 the enlargement or increase of bulk in 

 bodies, chiefly by means of heat. This 

 is one of the most general effects of ca- 

 loric, being common to all bodies what- 

 ever, whether solid or fluid, or in an aeri- 

 form state. In some cases bodies seem 

 to expand as they grow cold, as water in 

 the act of freezing ; this, however, is 

 known to be no exception to the general 

 rule, but is owing to the arrangement of 

 the particles, or to crystallization, and is 

 not a regular and gradual expansion, like 

 that of metals, or other solid substances, 

 by means of heat. In various metals, 

 likewise, an expansion takes place in 

 passing from a fluid to a solid state, 



which is accounted for in the same way. 

 The expansion of solids is exhibited by 

 the PYROMETER (which see.) A rod of 

 iron, for instance, becomes sensibly long- 

 er and larger in all its dimensions in pass- 

 ing from a low to a high slate of tempe- 

 rature. The expansion of fluids is shewn 

 by the thermometer, and is the princi- 

 ple upon which that useful instrument is 

 constructed ; by immersing a thermome- 

 ter into hot water, the mercury, or other 

 fluid, contained in it, immediately ex- 

 pands. See THERMOMETER. The degree 

 of expansion produced in different li- 

 quids varies very considerably. In ge- 

 neral, the denser the fluid, the less the 

 expansion ; water expands more than 

 mercury, and alcohol, which is lighter 

 than water, expands more than water. 

 The expansion of aeriform fluids may be 

 exhibited by bringing a bladder, partly 

 filled with air, and the neck closely tied, 

 near the fire ; the bladder will soon be 

 distended, and will, if the heat be strong 

 enough, burst. Metals expand in the 

 following order; those that expand most 

 are placed first : zinc, lead, tin, copper, 

 bismuth, iron, platina. 



EXPECTATION of life, a term used 

 by the writers on life annuities and rever- 

 sions, and which, according to Dr. Price, 

 signifies the mean continuance of any gi- 

 ven single, joint, or surviving lives, ac- 

 cording to any given table of observa- 

 tions : that is, the number of years, which, 

 taking them one with another, they actu- 

 ally enjoy, and may be considered as sure 

 of enjoying ; those who live or survive be- 

 yond that period enjoying as much more 

 time, in proportion to their number, as 

 those who fall short of it enjoy less. See 

 LIFE, duration of. 



EXPECTORANTS, an appellation gi- 

 ven to those medicines which facilitate 

 the discharging the contents of the 

 lungs. 



EXPECTORATION, the act of evacu- 

 ating or bringing up phlegm, or other 

 matters out of the trachea, lungs, &c. by 

 coughing, hauking, spitting, &c. 



EXPEDITION, in military affairs, is 

 cheifly used to denote a voyage or march 

 against an enemy, the success of which 

 depends on rapid and unexpected move- 

 ments. No rules have been, or probably 

 can be, given for the application of expe- 

 ditions generally ; they depend on cir- 

 cumstances that cannot be foreseen ; they 

 seem to depend on the following max- 

 ims : 1. Secrecy of preparation and con- 

 cealment of design. 2. The means must 



