DIA 
DIALTHEA, in Pharmacy, ia an ointment made (as 
its name imparts ) with the althza or marfh-mallow root. 
Tt is now diluted, 
DIALYSIS, or Diautsis, in Grammar, a chara&er con- 
filling of two points “ p! ‘taced over two vowels of a word, 
wiich would otherwife make a lati a are hereby 
parted into two fyllables : as in aic. See ERESIS, 
DIAM, in Geogr ace a town at Perfia, in ie province 
of Chorafan ; 80 mil of Her 
DIAMANT, LA, a wee of ie ifland of aa on 
the fouth coat. N. lat. 14° 26. W 60° 56 
D fenigieeaett set ee in Pharmacy, is an ancient 
lectua d of pearls and various aromatics. It is 
difufed . ae sae by the prefent aromatic co De 
DIAMARTYRIA, et in Antiquity icicle 
tation that the deceafed perfon h an heir, made to 
hinder the relations from oe soem the eftate. Potter, 
Archzol. Gree. tom i. lib. i. cap. Ras 3 128. 
DIAN LASTIGOSIS. It w cuftom among the 
Lacedemonians, at the Andes, of a vfeftival bear- 
ing this name, for the children of the molt diftinguifhed 
families to flafh and tear each others bodies with rods before 
, Not to give the leaft fign of pain, or concern 3 
(ae of them were fo feverely lafhed as . die upon the fpot. 
Such as were oo to ae ee were ae — 
they were buried, r ho- 
nour. They aft as eonead theme wit whipping 
their youths till the blood came. Dur mony t 
prieft held in his hand a ftatue of Diane Orthia. This Reed 
he defign hereof, apparent- 
o harden their youth, ar r 
them betimes to tien wounds, aa hae they might def- 
pife them Piliae they ca 
The cufom ral deteribed i is fd to have had its rife in 
confequence of a ordered that the altar 
of the ree at rere erg bs. Cala with ised. 
Accordingly they offered every year in facrifice a man cho- 
is for that purpofe. This was changed gi Lycurgus in- 
o the whipping of boys . ies altar. But when the boys 
were whipped to death, as the moft pi method of 
facrificing dene ; of a Plutarch, in his life of Lycur- 
acier, in his 
the women, 
young m boys round Diana’s altar at 
Sparta; and Potter, in “his Greek a whe that 
Bacchus had an altar in Arcadia, upon w eat many 
8. 
an of the older 
ambergris entered as an ingre- 
R, from Se and pepe, £0 ical in Geo- 
metry, a right t line piling through the centre of a circle 
and terminated on each fide by its circumfer 
Or, the diameter may be defined a chord nan through the 
centre of a circle. Such is the jag AE ( Plate ane vanienk 
Je 78.) pafling through the centre C. e the dia 
ter Is ae greatelt of allc abe nee ede: a line es 
than the diameter, drawn : any point within the 
will cut the circumference Fics it appears that a lin 
equal to a given line, tefs than the Sires of the a 
may be applied, or infcribed in a given circle. Hence alfo 
it appears, that if, to the circumference ie acircle AF EB, 
(fig. 79+) from any aa G, which is not the centre, ight t 
nes DA, DF, DE be drawn, the greateft of all, DA, 
7 
DIA 
wll be that which paffes through the centre C3 and of :he 
refi, pe DF, whofe other extreme, F, is placed reareft in’ 
the circumference to the extreme e greateft, will 
exer ned any other, oe 
diftance, ea e 
Sin 
Der. "Therefore D Fis is 
,0 
be paul to each i a ee ail right lines cannot poffibly 
be drawn from the periphery to any “point, befides the cen- 
tre of the circle ; and, therefore, if from a point in any circle, 
three equal right Hines can be: drawn to the riphery, 
hat point is the centre of the circle. Morcover, no habe 
can be defcribed to cut another in more points than two; for 
if it were poffible to cut it in three po a G,E, ¥, thew 
right lines drawn from the centre, Q, to thofe points bias 
be all equal, oe is eee unlefs when the centre Q__ 
coincides wit en the circles themfelves wiil 
neither cut, nor ick Bat coincide, and become one 
circle. 
Half a diameter, as CD, (fg. 78.) drawn from the centre 
» to the circumference, 15 called the femidiameter, or. 
BO 
2. 
The diameter divides the circumference inta equal parts. 
And hence we have a method of defcribing a femicircle upon 
any line ; affuming a.point therein for the centre. 
i IAMETER fo the el balan 
n Breally fought the mathematicians ; 
and no wonder; inafmuch as if ‘hi were it Bech, the 
quadrature of fe) gras were atchieved, 
Archimedes firft propofed a method of finding it, by re- 
gular poly ygons a ina ie till arriving oe fide fub- 
tending an ing {mall arc, and th king a fide 
. a _Aimilar pacie, eer a; dune of thefe being 
n whic 
of the circle is grea 
the perimeter of the circumfcribed polygons but leds eae 
that of the diameter e perimeter of the polygon 
cribed. ‘The difference between both gives the ratio of the 
diameter to pe circumference in numbers nea rly true. See 
Circe, art. 
That Gina eae as already obferved, by polygons 
of 96 fides, aie the ra oe the ire 
ference to .be as 7.to iz. fuppofing the diameter Ty 
the perimeter oe the ae polygon 1s found 35°, and 
that of the circumfcribed 31. 
After this example, later authors have found out ratios 
yet nearer truth ; Wolfius finds it as par ata pele 
in 31415926535897932 5 ; ae none fpent fo much tim 
eulen, who, after sect: pains, found that te 
poling “the “diameter, 1, the cir ircumferenee is lefs than 
reat~ 
er tha the fame number with only ‘the lait igor fo) changed 
Mr. A. Sharp doubled Van Ceulen’s numbers ; 
a this j is fo near the truth, that the diameter of oe earth 
being given, we might from thence compute the number of 
ue equal to the: folia contents of ied Beas fo near as beh 
to differ one grain of fan m the 
carried them to one heared lice 
of a circle whofe diameter is I, will be 3 
in 
thos the circumference 
3+-44159265358079 
if 
ry Beat VI T tI on TOS: FYAASIESD ail 19445 
QA QK GA~Q 4825 Pa 131 1170679. 
ae s fuch prolix numbers are too teldiy for prac- 
aay of our prefent practical geometric affume the 
diets to be to the circumference as 100 to 3145 or ip 
greater 
