diastole 
Most cues of diastole in latin poetry are supposed to lie 
ni-l.i'M > -> "I ivwTMMit 1., mi uhli i jiioiiuih lalhiii tlhMi'Ji 
the pause which usually follows couM <>f itself make good 
the metrical ilcticiciicy. This reversion Is seen chictly in 
verb-terminations with tiniil ( and r : u, 
Callidiis utsolcat hnmeris portare viator. 
lit/race, Satires, I. v. 90. 
diastolic (di-a-stol'ik), a. [< diastole + -ic.] 
I Vi'hiiiiiiig to or produced by diastole. 
diastolyt (di-as'to-li), n. An obsolete form of 
l//lf^/lt/C. 
Diastopora (di-a-stop'o-rii), n. [NL., for *Dia- 
stutoporu, < Or'.' dtdora'rofi split up, divided (< 
AaoTiywu, separate : see diasiasis), + iro^iof, pas- 
sage, pore.] The typical genus of the family 
Diastoporidae (dl-as-to-por'i-de), n. pi. [NL., 
< Diastopora + -idai.] A family of cyclo- 
stomatoug gymnolsematous polyzoans. 
diastyle (di'a-stil), a. [< L. diaxtylos, < Or. 6ia- 
arv'/jif, having the columns wide apart (whence 
dMer&Uoy, the space between columns), < Aid, 
apart, + OTMOC., a column : see style'*.] In arch., 
pertaining to that arrangement of columns in 
a classical order in which the intercolumniation 
measures three diameters. See cut under inter- 
COlumililllinn. 
Diastylidae (di-a-stil'i-de), n. pi. [NL., < Dia- 
atjilin + -id<f.] "A family of macrurous thora- 
costracous crustaceans, equivalent to the sub- 
order Cumacen of some authors, containing re- 
markable aniiectent forms related on the one 
Diitstytis ijHadrisfinosa. 
hand to schizopods, on the other to copepods, 
and exhibiting m some respects a persistence of 
a larval type of the higher Crustacea. They are 
ThonwostmiM or 1'odopMhalmia with a small cephalo- 
thoracic shield, typically 5 thoracic somites, 8 pairs of 
legs, of which at least the two anterior pairs are bira- 
inous or of the schizopod type, maxillipcds in 2 pairs, 
and the abdomen elongated, of 6 somites, and in the 
male bearing several pairs of swimming-feet besides the 
terminal appendages. Diastyli* and Lfltcon are leading 
genera. As understood by recent naturalists, it is limited 
to Diatttyli* and Leptuxtiflitt ; these have the integuments 
strongly indurated, Inxly ami tail sharply defined, and the 
carapace large and vaulted, with a conspicuous rostriform 
prominence. 
ylis (di-as'ti-lis), n. [NL., < Gr. Aidarv AOJ : 
see iliit.-itii/i .\ The typical genus of the family 
Diastylida;. 
diasyrm (di'a-sirm), n. [< Or. iiaavp/iof, dis- 
paragement, ridicule, in rhet. a figure of speech 
so called, < diaai'pciv, disparage, ridicule, tear in 
pieces, < <!i, apart, + o'vptiv, drag, draw.] In 
rlut., a figure of speech expressing disparage- 
ment or ridicule. 
diatessaron (di-a-tes'a-ron), n. [L., < Gr. 6ia- 
rcaadpuv, for >} <!<a rcaadpuv, sc. xl"^ v av/ujxjvia, 
the interval of a fourth (see diapason, diapente) : 
reaadpwv, gen. pi. fern, of rcooapef = E. four: 
see tessara and four.] 1. In Gr. and medieral 
music, the interval of a fourth. 2. [Gr. T& Aid 
reaedpuv (Tatian, in Eusebius).] A harmony of 
the four Gospels. The first work of this kind was that 
of Tatian (latter half of the second century), a Christian 
apologist, but afterward a Gnostic. 
Who would lose, in the conference of a Diatessaron, the 
peculiar charm which belongs to the narrative of the dis- 
ciple whom Jesus loved ? Macaulay, Boswell's Johnson. 
3. In old pliar., an electuary composed of four 
medicines : gentian, birthwort, bayberries, and 
myrrh Diapason diatessaron. See rfui/>am>u. 
diathermal (di-a-ther'mal), a. [< Gr. did, 
through, + Oepfi6s, heat, + -al. Cf. diatherman- 
ous.] Same as tliutlH-riimii/imt. 
diathermance, diathermancy (di-a-ther'- 
mans, -man-si), n. [< diatherman-ous H- -ce, -ey, 
after Gr. Oipfiavaif, heating, < Brpftaivttv, heat.] 
The property of transmitting radiant heat; the 
quality of being diathermanous. 
diathermaneity ((ri-a-tlior-ma-ne'i-ti), n. [= 
F. diathermaneitd ; as dialhn'iiian-oitg + -e-ity.~\ 
Same as diathermaiiee. 
diathermanism (di-a-ther'ma-nizm), n. [As 
diitllii'rnnni-ouis + -ism.] The transmission of 
radiant heat. 
diathermanous (dl-a-ther'ma-nus), a. [< Gr. 
fiiafapfiaivEiv (dtadtpitav-}, warm through, { tied, 
througli, -I- Oepfiaiveiv, warm, heat, < Oep/i6f, 
heat.] Freely permeable by heat. The term is 
^pecilieaUy applieil tn certain Ribuuiofll, such as crystal- 
line pieces uf rock-salt, etc., which sntfer railiant heat to 
p:lss through them, much in the same ay ;ts transparent 
i>r diaphanous bodies allow of the passage of li_ht. Sec 
absorption. Also diatherinal, diathermic, diathermoiu. 
1507 
diathermic (di-a-thcr'mik), a. [As ditttlierm-al 
+ -if.J Same as diatln rm".v 
In thin plates some descriptions tint the sun with a 
greenish hue : others make it appear a glowing red with- 
out any trace of green. The latter are by far more dia- 
HOTHH than tin former. Tyndall, Radiation, | 8. 
diathermometer (di'a-ther-mom'e-Wr), it. [< 
Gr. did, through, 4- fop/tof, heat, + pirpov, mea- 
sure.] An instrument for measuring the ther- 
mal resistance of a substance by noting the 
amount of heat which it transmits. 
diathermous (di-a-ther'mus), a. [< Gr. 6i&, 
through, + Ocp/i6f, heat.] Same as diather- 
manous. 
The diathermou* forenoon atmosphere. 
Amer. Jour. Sri., Whole No. mix. p. 890. 
diathesis (di-ath'e-sis), n. [NL., < Gr. oidBeaic, 
arrangement, disposition, state, condition (of 
body or mind), < iiariOtvat, arrange, dispose, 
place separately, < aid, apart, + nticvai, place, 
put. Ct.thettis.] 1. In wed., a predisposing con- 
dition or habit of body; constitutional predis- 
position : as, a struinous or scrofulous diathesis. 
She Inherited a nervous diathesis as well as a large 
dower of intellectual and aesthetic graces. 
JS. II. Clarke, Sex in Education, p. 98. 
2. A predisposing condition or state of mind ; 
a mental tendency ; hence, a predisposing con- 
dition or tendency in anything. 
In whichever rank you see corruption, be assured it 
equally pervades all ranks be assured It is the symp- 
tom of a bad social diathens. 
a. Spencer, Social Statics, p. 256. 
All signs fail in a drought, because the predisposition, 
the diathexia, is so strongly toward fair weather. 
The Century, XXV. 675. 
diathetic (di-a-thet'ik), a. [< diathesis (-thet-) 
+ -ic.] Of or pertaining to or dependent upon 
diathesis; constitutional: as, diathetic tumors. 
Diathetic diseases: that is to say, diseases dependent 
upon a peculiar disposition of iKxiy or mind, or l)oth. 
V. W. Richardton, Pi-event. Med., p. 6O5. 
diathetically (di-a-thet'i-kal-i), adv. In a dia- 
thetic manner; as regards diathesis, or consti- 
tutional predisposition ; constitutionally. 
Out of the serous layer is evolved the whole voluntary 
motor apparatus of hones, muscles, aponeuroses, liga- 
ments, and serous tissues ; so that . . . they are related 
to each other nutritionally and diathetically. 
E. C. Mann, Psychol. Med., p. 346. 
diatite (di'a-tit), n. [< diat(om) + -ite*.] A 
cement composed of a mixture of shellac and 
finely divided silica. 
diatom (di'a-tom), ii. A member of the Diato- 
macea. 1 Diatom prism. Sceprixm. 
Diatoma (di-at^o-mft), n. [NL., < Gr. as if 
*<5Sro//of, verbal adj. of Aiarifiveiv, cut through, 
< Aid, through, + riu- 
vtiv, rauclv, cut.] In 
hot., a genus of I>in- 
tomaeea!, in which the 
Diatoma, magnified. frustulesareconnect- 
ed together by their 
angles, forming a zigzag chain, and the valves 
composing them only meet at the edges with- 
out overlapping. There are about a dozen 
species, found on submerged plants and stones. 
Diatomaceae (di*a-to-ma'se-e), n.pl. [NL., < 
Diatoma + -acete.] ' An order of microscopic 
unicellular algte, much resembling the Desmldi- 
acece, from which 
they are distin- 
guished by a sili- 
cification of the 
cell-wall and by 
the presence of 
a brownish pig- 
ment which con- 
ceals the green 
of the chloro- 
phyl. The cells are 
cither isolated or 
united into threads, 
etc., and often se- 
crete a thin jelly 
in which they live 
socially. Each frus- 
tule is composed 
of two separate 
and similar parts 
(valves), the edges 
of which usually 
fit one over the 
other like the lid of 
a box. Repvoilnc- 
tion takes place, as 
lu the desmids, in ''"'" : . ''" ud ' n 
twn wnva liv illvi K lc "USttlle of Stnatfll, 
iwo ways OJ lllVI- showing striae; <-, Gtmfi 
sion and by sexual 
conjugation. Dia- 
toms exist in all 
parts of the world 
Diatomacta, magnified. 
a, young individuals of Cttfctmtma latt- 
ceotatum ti, longitudinal view of a sin- 
of Striatella tMtfrrufta. 
showing stria? ; f, Gompkottttna hynli- 
HMm. attached to a filament of CfttVfrVf f 
J. stritittll* intfrrupta : many indi- 
viduals united laterally to form a strap- 
shaped colony, with a lateral pedicel, 
f From Ue Maout and Decaisne's * Tralte 
in immense numbers general de Botanique." j 
diatribe 
at the bottom of the sea and of freh water, and an also 
I'inii'l .iii.u n. ! I" '' plants, 
etc., and among mosses anil in -'i i dftop ! ulitie*. 
'I hi-rc arc many ^cm la, ;ucl tin- nnmliuruf known species 
exceeds 1,500. They vary greatly In the form and mark- 
ings of the valves, which are often i \ijin-it> 1> sculptured, 
funning iK-autiful obje^U mnlcr the microscope and test- 
ing its highest powers. In some species the lines are found 
to equal 125,000 to the inch. Extensive fosnil deposits of 
the siliclous remains of Itiatamacrtr occur In various lo- 
calities, as at Bilin in Bohemia, and In Virginia, .Nevada, 
ami California. They are sometimes used as polishing- 
jinuilcr. They are abundant in guano. Also called Ba- 
cinriate<K. 
diatomacean (di'a-to-ma'se-an), n. [< diato- 
maee-ous + -ait.] In hot., a plant of the order 
Diatomucete. 
diatomaceous (dl'a-to-ma'shius), a. [< Diato- 
maccce + -ous.] Iri'bot., belonging to or resem- 
bling Diatomacete. 
During the voyage of the Challenger, a ... diatnmaeewu 
ooze was found, as a pale straw-coloured deposit, in certain 
parts of the Southern Ocean. Huxley, Physlog., p. 232. 
diatomic (di-a-tom'ik), a. [< Gr. ii-, two-, + 
dro/iof, atom, + -ic.] In cnem,, consisting of 
two atoms: as, a diatomic radical: specifically 
applied to hydrates which have two hydrogen 
atoms united to the nucleus radical by oxygen. 
It is these hydrogen atoms alone which are 
easily replaced by metallic bases or other rad- 
icals. 
Tlie alcohols and fat acids are monatomlc, the glycols 
are diatomit, and the glycerines are triatomlc compounds. 
J. P. Coolie, chera. 1'hilos., p. 117. 
diatomiferous (di'a-to-mif'e-rus), a. K NL. 
IHatoma + L./erre"='E. beiir 1 , + -ous.] Con- 
taining or yielding diatoms. 
diatomin, diatomine (di-at'p-min), n. [< dia- 
tom + -iV-8, -ine 2 .] The buff or yellowish-brown 
pigment which colors diatoms and brown algae, 
obscuring the chlorophyl. Also called pliyco- 
rttntliinc. 
diatomist (di-at'6-mist), 11. [< diatom + -ist.] 
A botanist who 'has made a special study of 
the Diatomaeece. 
diatomite (di-at'o-mit), ti. [< diatom -f -ite?.] 
Diatomaceous earth ; infusorial earth. 
diatomoscope (di-a-tom'o-skop), n. [< NL. 
Diatoma + Gr. anoireiv, view.] An instrument 
for the examination of diatoms. 
diatomous (di-at'o-mus), . [< Gr. as if *iid- 
ro/iof, verbal adj. o'f itart/ivcir, cut through : see 
Diatoma.'] In mineral., having crystals with 
one distinct diagonal cleavage. 
diatonic (di-a-ton'ik), a. [= F. diatonique = 
Sp. diatonico = Pg. It. diatonico (cf. D. Gr. dia- 
tonisch = Dan. Sw. diatonisk), < LL. diatonieus, 
< Gr. itarovinov, also simply iidrovov (sc. Jf'vof, 
class), the diatonic scale, neut. of didrovof, ex- 
tending through, < itareivrtv, stretch through, 
extend, < tid, through, + reiveiv, stretch, > rovoc, 
tone: see tone.] 1. In (Ir. nnifrif, noting one 
of the three standard tetrachords, consisting 
of four tones at the successive intervals of a 
half tone, a tone, and a tone: distinguished 
from chromatic and enliarmonic. See tctracliord. 
2. In modern m ttsic, using the tones, intervals, 
or harmonies of the standard major or minor 
scales without chromatic alteration. Diatonic 
Instruments, instruments constructed to produce only 
the tones of the standard major or minor scales of their 
fundamental tone. Diatonic melody, a melody with- 
out modulation. Diatonic modulation, a modulation 
to a closely related key. See i'K'n<ari'n. DlatomcprO- 
gression, a melodic passage in which the tones uf the 
standard scale, major or minor, are used In succession up- 
ward or downward. Diatonic scald, a standard scale, 
major or minor. See wafe. 
diatonically (di-a-tou'i-kal-i), adv. In a dia- 
tonic manner. 
diatonous (di-at'o-nus), a. [< Gr. tidrovof, 
extending through': see diatonic.] Extending 
from front to back: in masonry, said of stones 
which extend entirely through a wall so that 
they appear on both sides of it. 
diatribat, Same as diatribe, 1. 
I have read y learned Diatriba concerning Prayer, & 
do exceedingly prayse your method. 
Eeelyn, To Mr. E. Thurland. 
diatribe (di'a-trib), n. [Formerly also, as L., 
diatriba ; = f. diatribe = Sp. diatr'iba = Pg. dia- 
tribe = It. diatriba, < ML. diatriba, a disputa- 
tion (L. diatriba, a school), < Gr. 6iarptj}i/, a wear- 
ing away, pastime, way of spending time, a 
school, a discussion, waste of time, < iiarpipeiv, 
rub away, waste, spend time, discuss, < ota, 
through, + rpifietv, rub: see trite.] 1. A con- 
tinued discourse or disputation. 
I have made ... a diatribe on the subject of descrip- 
tive poetry. Lovxll, Among my Books, 2d ser., p. 132. 
Specifically 2. A bitter and violent criticism ; 
a strain of invective. 
