transilient 
transilient (tran-sil'i-ent), a. [< L. transili- 
i'n(t-)s, ppr. of transilire, transsilire, leap or 
spring across or over, < trans, over, + xnlire, 
leap, jump: see salient.'] Leaping or extend- 
ing across, as from one base of support to an- 
other. Transilient fibers, nerve-fibers passing from 
one convolution of the brain to another not Immediately 
adjacent. 
transillumination (traus-i-lu-mi-na'shgu), n. 
[< L. trans, through, + LL. iHuminatio(n-), illu- 
mination.] A shining through ; the process of 
causing light to pass through; specifically, in 
med., the throwing of a strong light through 
an organ or portion of the body as a means of 
diagnosis. 
It [a tooth] was translucent by electric IransUlumina- 
tion, showing that the pulp was living. 
Lancet, 1S90, 1. 480. 
transincorporation (trans-in-kor-po-ra'shon), 
H. [< trans- + incorporation.'] Transmigration 
of the soul ; metempsychosis. [Bare.] 
Its contents are full of curious information, more par- 
ticularly those on the transincorporation of souls. 
W. Robberds, Memoir of W. Taylor, II. 305. 
transinsular (trans-in'su-lar), a. [< L. trans, 
across, + insida, island: see insular.'] Inanat., 
traversing the insula of the brain: said of a 
fissure of the island of Keil. Buck's Handbook 
of Med. Sciences, VIII. 149. 
transire (trans-i're), H. [< L. transire, go across, 
cross over: see transient, transit.'] A custom- 
house permit to let goods pass or be removed. 
Anderson, Law Diet. 
transischiac (trans-is'ki-ak), a. [< trans- + 
ischiac.] Extending transversely from one is- 
chiac bone to the other: as, the transisehiac 
diameter of the pelvic outlet. 
transisthmian (trans-ist'mi-an), a. [< L. trans, 
across, + isthmus, isthmus.] Extending across 
an isthmus : used chiefly with reference to the 
isthmus of Suez, or to that joining North and 
South America. 
A trans-isthmian canal will be a military disaster to the 
United States. The Atlantic, LX VI. 822. 
transit (tran'sit), n. [< F. transit = Sp. trdn- 
sito = Pg. transito = It. transito, a going over, 
a passing, passage, transition, < L. transire, pp. 
transitus, go across, pass: see transient. Cf. 
exit, circuit. See also trance^, trance 2 .] 1. The 
act of passing; a passing over or through; a 
passage ; the act of moving, or the state of being 
conveyed; also, the act or process of causing 
to pass; conveyance: as, the transit of goods 
through a country; the problem of rapid tran- 
sit in cities. 
For the adaptation of his [man's] moral being to an ulti- 
mate destination, by its transit through a world full of 
moral evil, the economy of the world appears to contain 
no adequate provision. WheweU. 
The necessity of subjecting the thousands of tons of pro- 
visions consumed daily by a large army to such long and 
complicated transits limits the transportation by wagons 
considerably, and renders the powerful assistance of steam 
indispensable, both by water and by rail. 
Comte de Paris, Civil War in America (trans.), I. 202. 
2. A line of passage or conveyance through a 
country: as, the Nicaragua transit. 3. In as- 
tron.: (a) The passage of a heavenly body 
across the meridian of any place. The right 
ascension of such a body is the sidereal time 
of its upper transit. (6) The passage of a ce- 
lestial body (specifically either of the planets 
Mercury and Venus) across the sun's disk, or of 
a satellite, or the shadow of a satellite, across 
the face of its primary. The passage of the 
moon across the sun's face, however, is called 
an eclipse. The planet Mercury passes across the sun's 
face usually at intervals either of 13 or of 7 years, tran- 
sits at the planet's ascending node occurring in Novem- 
ber, and those at the descending node in May. November 
transits have occurred or will occur in 1651, 1664, 1677 
1690, 1697, 1710, 1723, 1736, 1743, 1756, 1769, 1776, 1782, 1789, 
1802, 1815, 1822, 1835, 1848, 1881, 1868, 1881, 1894, 1907, 1914, 
1927, 1940, 1953, 1960, 1973, 1986, 1999, and May transits in 
1674, 1707, 1740, 1753, 1786, 1799, 1832, 1845, 1878, 1891, 1924, 
1937, 1970, 2003. Owing to the proximity of Mercury to 
the sun, its transits do not have the astronomical impor- 
tance of those of Venus, as they are less suitable for de- 
termining the solar parallax. Transits of Venus occur at 
intervals of 8, 122, 8, 105, 8, 122, . . . years, and always in 
June or December. They are of great importance to the 
astronomer, for they afford an excellent method of deter- 
mining the sun's parallax. The actual calculation of this 
from a transit is very intricate, as many slight corrections 
and sources of error have to be considered. The prin- 
ciple involved, however, will be understood from the dia- 
6432 
pram, in which Alt represents the earth, and V and S Ve- 
nus and the, sun. Observers at A and B see Venus pro- 
jected on the sun's disk at A' ami IV respectively, the 
observations being made simultaneously. The apparent 
portions A', B' are carefully determined by photography, 
by micrpmetric measures, or otherwise ; and a subsequent 
comparison of notes gives the angle a. If R and r denote 
the respective distances of the earth and Venus from the 
sun, the angle <8 is given by the equation a. : 3 = r : R. The 
ratio r : R is known with great precision from the sidereal 
periods of Venus and the earth, and since a was found by 
observation, the foregoing equation determines ft. The 
angle AB'B (being the angle subtended by the earth's di- 
ameter at the sun's distance) is equal to double the solar 
parallax, or to 2ir. From the triangle AVB' it follows that 
= a + 2ir, or ir = t (0 - a) = }a (U/r 1). The transit of 
176!) was observed by expeditions sent out expressly for 
the purpose by the British, French, Russian, and other 
governments. The celebrated expedition of Captain Cook 
to Otaheite was one of them. The transits of December 
8th, 1874, and December Cth, 1882, were also observed by 
various government expeditions. The next two transits of 
Venus will take place on June 8th, 2004, and June 6th, 2012, 
respectively. The satellites of Mars, I'ranus, and Neptune 
are too small to be seen in transit, and even Titan is an 
unsatisfactory object to follow across the face of Saturn. 
Great interest attaches, however, to transits of the satel- 
lites of Jupiter, or of the shadows of these satellites. 
When one of them crosses a dark belt it can usually be 
followed entirely across the disk as a round shining spot. 
The brightness of the satellites is variable, however, and 
sometimes they look like dusky or even black spots when 
seen against the disk of the planet. The transit of a 
satellite's shadow is readily observed. The shadow may 
be on the disk when the satellite casting it is oil, or the 
two may be seen on the disk at the same time. The shad- 
ows are not always black, but are sometimes so bright 
as to be invisible. They are often, and perhaps usually, 
different in size from the satellites casting them; and 
they have repeatedly been seen elliptical in outline. On 
a few occasions comets are thought to have been seen in 
transit. 
4. An abbreviation of transit-circle or transit- 
instrument. 5. An 
instrument used in 
surveying for mea- 
suring horizontal 
angles. It resembles 
a theodolite, but is not 
intended for veiy pre- 
cise measurement. Most 
transits read only to the 
nearest minute of arc, 
though some read to the 
nearest half-minute, or 
twenty seconds, or even 
ten seconds. Lower 
transit. Same as sub- 
polar transit. Stop- 
page in transit. See 
stoppage. Subpolar 
transit, a transit across 
that part of the merid- 
ian which lies below the 
pole. Upper transit, 
a transit across that part 
of the meridian which 
lies above the pole, or 
on the zenith side of it. 
Transits are always un- 
derstood to be upper, 
unless distinctly 
subpolar. 
-J 
Transit of Venus 
Surveyors' Transit. 
rr -., , tripod stand; *, leveling-plates; c, 
ailed leveling-screws; d, tangent screws ; e, 
clamping-screws; /, vernier; g, com- 
- .. pass; A, A', levels; i, vertical circle; 
transit (transit), y, clamping-screw; *, telescope. 
v. t. [< transit, .] 
To pass over the disk of, as of a heavenly 
body. 
It was also well known that Venus would transit the 
northern part of the sun during the forenoon of the 9th 
of December, 1874. Science, XVI. 303. 
transitationt, >< Passage; lapse. 
He obuiated a rurall person, and interrogating him con- 
cerning the Transitation of the time, . . . found him a 
meere simplician, whereas if in his true speech he had 
asked him what was the clocke, . . . his ignorance might 
of the simplician haue beene informed. 
Verstegan, Rest, of Decayed Intelligence (ed. 1628), 
[p. 205. 
transit-circle (tran'sit-ser"kl), n. An astro- 
nomical instrument for observing the transit 
of a heavenly body across the meridian, it 
consists of a telescope mounted upon a fixed axis which 
is perpendicular to the plane of the meridian and carries 
a finely graduated circle. In the sidereal focus of the 
telescope cross-wires are placed ; by observing the in- 
stant at which a star passes the center of the field of 
view, and, taking the corresponding reading of the circle, 
the right ascension and declination of the object are de- 
termined if the clock error is known ; or, vice versa, the 
clock error and latitude of the observer are determined 
if the right ascension and declination of the star are 
known. The instrument is now more usually called the 
meridian-circle (which see). Compare transit-instrument. 
transit-compass (trau'sit-kum'pas), H. Same 
as transit, 5. 
transit-duty (tran'sit-du"ti), H. A duty paid 
on goods that pass through a country. 
transit-instrument (trau'sit-in'stro-ment), n. 
An astronomical instrument for observing the 
passage of a celestial body across the meridian : 
often used in the same sense as transit-circle, 
but properly an instrument whose chief object 
is the determination of the time of transit. 
The circle fixed to the axis of the ordinary transit-instru- 
ment is intended simply as an aid in setting the instru- 
transitionally 
ment properly, and not for the determination of zenith 
distance or declination. The idea of having an instru- 
ment fixed in the plane of the meridian is as old at least 
as the time of Ptolemy. The first transit-instrument, as 
the word is now understood, was constructed in Kih!) by 
the Danish astronomer Olaus Roemer. In 1704 Roomer 
constructed a private observatory near Copenhagen, into 
which he put a transit-instrument combined with a verti- 
cal circle for measuring declinations. This was the first 
transit-circle made. Prime vertical transit-Instru- 
ment. See pritne. 
transition (tran-sish'on), n. [< F. transition = 
Pr. transitio = Sp. transicion = Pg. traitftifao = 
It. transitions, < L. transitio(n-), a passing over 
or away, < transire, go or pass over: see transi- 
ent, transit.] 1. Passage from one place, state, 
or act to another; change: as, a sudden trans- 
ition from anger to mirth ; a state of transi- 
tion. 
Thence, by a soft transition, we repair 
From earthly vehicles to these of air. 
Pope, R. of the L., i. 49. 
What sprightly traiutitinns does she make from an 
opera or a sermon to an ivory comb or a pincushion ! 
Addison, Spectator, No. 45. 
When Bunyan passed from this horrible condition [of 
doubt] into a state of happy feeling, his mind was nearly 
overthrown by the transition. Southey, Bunyan, p. 33. 
2. In rliet., a passing from one subject to an- 
other. 
80 here the archangel paused 
Betwixt the world destroy'd and world restored. . . . 
Then, with transition sweet, new speech resumes. 
Milton, P. L., xii. 5. 
3. Ill music, same (usually) as modulation. 
Sometimes, however, the term is used more precisely 
either for a sudden, abrupt shift from one tonality to 
another unrelated to it, or for a modulation without 
change of mode. The latter is the technical usage of the 
tonic sol-faists. 
4. In gcol , the English form of the name (used 
attributively or as an adjective) given by Wer- 
ner to certain strata which he investigated in 
northern Germany, and found to have, to a cer- 
tain extent, the mineral character of the so- 
called primitive rooks, while also exhibiting 
indications of a mechanical origin, and even 
containing occasional fossils, thus indicating 
a transition or passage from primary to secon- 
dary. The name was afterward extended so as to em- 
brace rocks of similar character in other regions. The 
argillaceous sandstone called by the Germans yrauwaclte 
(see graywacke) formed a part of the transition formation, 
and it was the rocks previously called yrauwacke and 
transition limestone which Murchison studied in Eng- 
land and Wales, and to which, having worked out their 
order of succession, he gave the name of Silurian. See 
Silurian. 
5. In art hist., an epoch or stage of change 
from one style or state of development in art 
to the next succeeding; especially, in Greek 
art, the stage of change from the archaic to the 
bloom of art, and in medieval art, that from 
the round-arched or Romanesque to the Point- 
ed style. Transition resistance. See resistance. 
Transition-tint See specific rotatory power, under ro- 
tatory. Transition tumor, a tumor which, upon recur- 
ring after removal, tends to assume a malignant form. 
transitional (tran-sish'on-al or -sizh'on-al), a. 
[< transition + -n/.] 1. Of or pertaining to 
transition; containing, involving, or denoting 
transition; changing; passing: as, the trans- 
itional stages of a tadpole ; the transitional 
plumage of a molting bird. [The word may have a 
strong sense, \\Viemetanwrphicortran9mutational (see def. 
3), but is usually much weaker, and more nearly synony- 
mous with transitory or transient.] 
One of the commonest transitional rocks deserves in 
several respects a further description. 
Darwin, Geol. Observations, i. 66. 
At Parenzo, the real charm is to be found in the traces 
which it keeps of the great transitional ages when Roman 
and Teuton stood side by side. 
E. A. Freeman, Venice, p. 100. 
Every period, however original and creative, has a 
transitional aspect in its relation to the years before and 
after. Stedrnan, Met. Poets, p. 14. 
2. Ill liol., of intermediate or intergraded char- 
acter between two or more species, genera, 
etc., and thus, as it were, exhibiting or illus- 
trating a transition from one to another form 
of organic life; transmutatioiial: as, a transi- 
tional specimen ; also, pertaining to or effect- 
ing such transmutation : as, a transitional the- 
ory; a transitional process. 3. Specifically, in 
art, relating to, characterizing, or belonging to 
an epoch or stage of change from one style or 
state of development to the next succeeding, 
and especially to that between archaism and 
full development in Greek art, and to that 
between the Romanesque and the Pointed in 
medieval art Transitional epithelium. See epi- 
thelium. 
transitionally (tran-sish'on-al-i or -sizh'on- 
al-i), adv. In a transitional manner. Nature, 
XLI. 514. 
