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Chambers, Ephraim, 1680 (ca.)-1740 / Cyclopædia, or, An universal dictionary of arts and sciences : containing the definitions of the terms, and accounts of the things signify'd thereby, in the several arts, both liberal and mechanical, and the several sciences, human and divine : the figures, kinds, properties, productions, preparations, and uses, of things natural and artificial : the rise, progress, and state of things ecclesiastical, civil, military, and commercial : with the several systems, sects, opinions, &c : among philosophers, divines, mathematicians, physicians, antiquaries, criticks, &c : the whole intended as a course of antient and modern learning
(1728)

Teller - thrave,   pp. 190-209 PDF (19.2 MB)


Page 190


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df Metallic 'bnes; adding, that there Is Nothing more re-
quir'd to the Perfection of this Telefcope, but that the Art
of polifhing Glafs be brought to greater Perfeaion ; for
that fome Inequalities which don't hurt Lens's, are found
to afFe& Specula, and prevent Objecs being feen diflinatly.
The fame Author obferves, that if the Length of the in-
firument be 6 Feet, and confequently the Semi-diameter of
the Concave Speculum 12, the Aperture of the Speculum is
to be 6 Inches; by which Means the Object will be increas'd
in the Ratio of i to zoo or 300.
If it be longer, or Ihorter, the Aperture muaR be as the
Cube of the Quadrato quadrate Root of the Length, and
its magnifying Power as its Aperture. The Speculum he
orders to be an Inch or two broader than the Aperture.
A4erialTELEscoPE, a kind of Afironomical  felefcope, the
Lens's whereof are us'd without a Tube.
In Strictnefs, however, the Aerial lielefcope, is rather a
particular Manner of mounting and managing long l'elef-
copes, for Creleflial Oblervations in the Night Time, where-
by the Trouble of long unweildy Tubes is fav'd, than a
particular Kind of 7elefcope. The Contrivance we owe to
the noble Huygens.
Conflruion of the Aerial TEitEsCOPE.
Io A tall Pole or Malf, A B (Fig. 46.) the Length the
Tube fhould be of, is fix'd perpen icularly in the Ground.
Before the ereffing it, one Side is planed fmooth, and upon
it two Rulers fix'd parallel to each other, an Inch and Half
apart, including a kind of Groove or Channel between them,
reaching from top almofl to bottom. At the Top of the
Pole is fitted a little Truckle A, moveable on its Axis, and
over it is drawn a Cord G g, double the Length of the Pole,
and the Thicknefs of the little Finger, returning into itfelf,
and furnilh'd with a piece of Lead, H, equal in Weight to
the Lens and a moveable Arm to be fuflained thereby.
Then, a wooden Lath, CD, two Foot long, is framed fo
as that it may Ride freely in the Channel; and in the Middle
thereof, is affix'd a wooden Arm E, flanding out a Foot from
the Pole, and on its Extremity bearing another, F f, a Foot
and Half long, fix'd to it at Right Angles ; both of them
parallel to the Horizon.
20 An Objea-glafs is included in a hollow Cylinder I K,
three Inches long: To this Cylinder is fix'd a Staf, K L,
near an Inch thick, and a Foot long, which rells on a brafs
Ball M, that moves freely in its Cup or Socket underneath:
Only, on Occafion, the Ball and Soclet are fix'd by a Screw.
That the Lens thus equally balanced, may be moved with a
fmall Force, a Weight N I of about a Pound, is fufpended,
by a firong Wiar NF, by bending which, the common
Centre of Gravity of the Weight, the Lens is eafily made to
coincide with that of the Ball. To the Staff KL, is fix'd
a brafs Style L, which is bent downwards, till its Point be as
much below the Centre of the Staff, as the Centre of the
Ball is. To the Point is tied a fine filken Thread L V,
which, of Confequence, will be parallel to the StaffK L.
30 An Eye-glafs 0, is included in a Ihort Cylinder; and
the Staff P V, fix'd to the fame. To this is hung a little
Weight S. fufficient to make a Balance. In Q is fix'd a
Handle, R, which carries a tranfverfe Axis, to be held in the
Obferver's Hand, and the Staff P V diredled towards the
Object-glals, is tied to the Thread L V. The Thread pafs'd
through a Hole, V, is wound about a little, Peg T, fix'd in
the middle of the Staffl; by the turning whereof, the Length
of the Thread is lhorten'd or prolong'd at Pleafure.
40 That the Obferver may be able to hold the Eye-
glafis Ready; he has a Fulcrum or Prop under his Arm, the
Struafure whereof appears from Infpealion of the Figure.
La"ily, to keep off the feeble Light flowing from the Air upon
the Eye, it is conveniently cover'd with a Circle, Y, perfo-
rated in the Middle, fitted on to a moveable and flexible
Arm
TELESCOPICALStars, arefuch as are not vifible to the
naked Eye; but difcoverable only by the Help of a Telefcote.
See STAR.
All Stars lefs than the 6th Magnitude, are Telefcotic to a
moderate Eye.
TELLER, an Officer in the Exchequer, of which there
are Four. See EXCHEQ<_ER.
Their Bufinefs is to receive all Monies due to the Crown,
and thereupon to throw down a Bill through a Pipe, into the
Tally-Court, where it is received by the Auditor's Clerks,
who attend there to write the Words of the faid Bill upon a
Tally; and then deliver it to be enter'd by the Clerk of the
Pells, or his Clerk. See TALLY and PELL.
The Tally is then fplit or cloven by the two Deputy Cham-
berlains, who have their Seals, and whilfl the Senior Deput
treads the one Part, the Junior examins the other Part, witC
the other two Clerks.                  A
Their Places are in the King's Gift, and they have, befides
their chief Clerk or Deputy, four other Clerks, for the Dif-
Kat~1~ ot Bufinefs,
T.E M
TELLUS, Zerra; t, in Aftronomy. See EARTAL
TEmPERAMIENT
CPhYla      )         (TEM ERAMEtNT
TEMPER in aMuPhfical       Senfe. Skie TEM  uBAMINC
Mechanical          e    n Mufic.
TEMPERAMENT, T'EMPERAME9TUM, TEM-
PERATURE, in Phyficks, that Habitude or Difpofition of
a Body arifing from the Proportion of the feveral prime or
elementary Qualities it is compofed of. See QUALITY and
ELEMENT.
The Notion of Temperament, arifes from that of Mixture,;
where different Elements, as Earth, Water) Air and Fire (or,
to fpeak more jufily, in the Peripatetic Way, hot, cold, moiff
and dry) are blended together; by their Oppofition, they tend
mutually to weaken and incroach on each other: and from the
whole, arifes a fort of temperate Crafis, or Coalition of them
all, in this, or that Proportion; whence, according to the
Quality that prevails or predominates, we fay a hot or cold,
a moiji or dry Tiemperament.
It is controverted among the School-men, Whether th6
mperament properly comprehends all the Pour primary
Qualities ? or, Whether thofe do not all ceafe, and a new one,
a Fifth, fimple Quality, refult from the total Alteration made
in the other Four, by their mutual Affion on each other?
Authors diflinguifhl two Kinds of temperaments, viz.
Uniform and fDifform: The Firfl, wherein all the Qualities
are rnix'd in an equal Degree: The Second, where in an un-
equal one.
The Uniform  'emPerameeni, can only be one; the Diffbrni
admits of Eight different Combinations, fince either any one;
or any two of the Qualities may prevail i whence hot and
moifi, cold and moifi, Ac. Further, fome confidering that
the Qualities which do prevail, may not be in equal Degree;
and the like of rhofe which do not prevail; make feveral
other Combinations or Iemeraments; and add 12 more to
the Number. In effe&, as there are infinite Degrees between
the highefi and lowefl Pitch of any one of the Elements,
the different Temperatures may be faid to be Infinite.
TEMPERAMENT, in Medicine, is particularly underflood
of the natural H-abitude and Conflitution of the Body of
Man; or the Difpofition of the Animal Humrours. See CON-
STITUTION and HUMOUR.
The Notion of this Temperament arifes hence, that the
Blood flowing in the Veins and Arteries, is not conceived to
be a fimple Fluid; but a fort of imperfedt Mixt, or an
Afiemblage of feveral other Fluids. For it does not only
confiff o the Four fimple, or primary Qualities; but of
Four other fecondary Ingredients compounded thereof, into
which it is fuppofed to be refolvable viz., Choler, Phlegmi
Melancholly and BIlood, properly fo called.  See BLOOD;
CHOLEiv, BILE, PHLEGM, )c.
Hence, as this, or that Ingredient Humour prevails in a
Perfon, he is faid to be of a Choleric, Phlegmatic, Melan-
cholic, Sanguine, &c. femperamen:. See SANGUINE, ME.
LANCHOLLY, CHOLERIC, UC.
The ancient Phyficians brought thefe Animal Tempera-
ments to correfpond with the univerfal r'emPer.4ments above
defcribed: Thus the Sanguine Temperament was fuppofed td
coincide with hot and moi.i; the Phlegmatic with cold and
moigf, the Melancholic with dry and cold, ec.
Galen introduced the Dodrine of  temperamenns into
Phyfic, from the Peripatetic School; and made it, as it were,
the Bafis of all Medicine. The whole of curing Difeafehs
confifled in tempering the Degrees of the Qualities, Hu
mours, fec. See GALENICAL, DEGREE, Cc.
On the Footing Medicine now ftands, the Temperaments
are much lefs conlider'd. Dr. fiuincy and other Mechanical
Writers, pare away the greate I"art of the Galenic Notionj
as ufelefs and uncertain; and confider the Temperaments as
no other but thofe Diverfities in the Blood ofdiRerent Perfonso
whereby it becomes more apt to fall into certain Combinations
in one Body than another, whether into Choler, Phlegm,
Cc. whence, according to them, People are denominated
Choleric, Phlegmatic, &c.
The Ancients diflinguifh'd two Kinds of Temperaments
in the fame Body; the one ad Pondus, in Weight; the other,
ad ufitiam.
The Temperamentum ad Tondus, is, where the elementary
Qualities are found in equal Quantities, and in equal Propor-
tions; fuch is fuppofed to be in the Skin of the Fingers;
without which they would want Power of diffinguilhing
Objefs, with fufficient Accuracy.
The Temperamentum ad  fuftiiam, is that which contains
unequal Portions of thofe Qualities, but yet in fuch Pro-
portion as is neceffary for the Difcharge of the Fun&ions
proper to the Part: Such is the _Temperament in a
Bone, which contains more earthy than aqueous Parts,
to make it more hard and folid, for its Office of fullain-
ing,
Gales
T E L


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