H E B 
HED 
H E A 
Among medalists, the different heads on 
ancient coins, are distinguished by the dif- 
ferent dresses. See Medal. 
In the imperial medals, where the head is 
quite bare, it is usually a sign the person ! 
was not an emperor, but oite of the children ! 
of an emperor, the presumptive heir of the.; 
empire. Tlie heads which are covered, are i 
either covered with a diadem, or a crown, or j 
a simple cork, or a veil, with some other fo- | 
reign covering, whereof the diadem is the j 
most autient. The heads of deities are dis- 
tinguished by some special symbol. 
Head-ache. See Medicine. 
HEADBORROYY, or Headborougk, 
the chief of the frankpledge, and he that i 
had the principal government of them within ! 
his own pledge. And a< he was called head - : 
borrow, so was he called burrowhead, burs- j 
holder, thirdborrow, tithingman, chief- i 
pledge, or borrow-elder, according to the di- ! 
versity of terms in several places. The same 
officer is now occasionally called a consta- 
ble. The headborough was the chief o f the 
ten pledges: the other nine were called hard- 
boroughs, or inferior pledges. 
Head-lin es, in a ship, those ropes of all 
sails which are next to the yards, and by 
which the sails are made fast to the yard. 
Head-sea, is when a great wave or billow 
of the sea comes right ahead of the ship, as 
she is in her course. 
Head-sails, in a ship, those which be- 
long to the fore-mast and boltsprit: for it is 
by these that the head of the ship is governed, 
and made to fall off and keep out of the 
wind; and these in quarter- winds are the; 
chief drawing sails. 
Head of a ship, or other vessel, is the 
prow, or that part which goes foremost. 
Dragon's Head, in astronomy, &c. is the 
ascending node of the moon, or other planet. 
See Node. 
HEARING, the sense whereby we per- 
ceive sounds. See Anatomy, Physiolo- 
gy, and Sounds. 
HEARSAY, is generally not to be admit- 
ted as evidence; for no evidence is to be al- 
lowed but what is upon oath; for if the first 
speech was without oath, another oath that 
there was such speech, makes it no more than 
a bare speaking, and so of no value in a court 
of justice; and besides, the adverse party has 
no opportunity of a cross-examination; and 
if the witness is living, what he has been heard 
to say is not the best evidence that the nature 
of the thing will admit. But in some cases 
hearsay evidence is allowed to be admissible; 
as to prove who was a man’s grandfather when 
he married, what children he had, and the 
like ; of which it is not reasonable to presume 
that there is better evidence. So in ques- 
tions of prescription, it is allowed to give 
hearsay evidence, in order to prove general 
reputation ; as where the issue was of a right 
to a way over the plaintiff’s close, the de- 
fendant was admitted to give evidence of a 
conversation between persons not interested, 
then dead, wherein the right to the way was 
agreed. Theory of Evid. 111. See ‘Evi- 
dence. 
HEARSE. See Hind. 
HEART. See Anatomy. 
HEAT, in physiology. See Caloric. 
Heat, Animal. See Respiration. 
Heat, in geography, the diversity of 
the Rent of climates and seasons arising 
chiefly from the different angles under which 
the sun’s rays strike upon the surface of the 
earth. Dr. Halley gives a mathematical com- 
putation of the effect of the sun under the 
different seasons and climates. Let it, how- 
ever, be considered, that the different degrees 
of heat and cold in different places depend in 
a very great measure upon the accidents of 
situation, with regard to mountains and val- 
leys, and the soil. The first greatly helps to 
chill the air by the winds which come over 
them, and which blow in eddies through the 
levels beyond; and mountains, sometimes 
turning a concave side to the sun, have the 
effects of a burning mirror upon the subject 
plain ; and the iike effect is sometimes had 
from t'ne convex parts of clouds, either by 
refraction, or reflection. As to soils, a stony, 
sandy, or chalky earth, it is known, reflects 
most of the sun’s rays into the air again, and 
retains but few, by which means a consider- 
able accession of heat is derived to the air ; 
as, on the contrary, black loose soils absorb 
most of the rays, and return few into the air, 
so that the ground is much the hotter. 
The following table of the heat of different 
climates is computed for every tenth degree 
of latitude, to the equinoctial and tropical 
sun ; by which an estimate may be made of 
the intermediate degrees. 
Lat. 
Sun in 
cy> 
Sun in 
£5 
Sun in 
0 
20000 
18341 
18841 
10 
19695 
20290 
15854 
20 
18797 
21787 
13166 
SO 
17321 
22651 
10124 
40 
1.7321 
23048 
6914 
50 
12855 
22991 
3798 
60 
10000 
22773 
1075 
70 
6840 
23543 
000 
80 
8473 
24673 
000 
90 
0000 
25055 
000 
Hence are deducible the following corol- 
laries. 1. That the equinoctial heat, when 
the sun becomes vertical, is as twice the 
square of the radius, which may be proposed 
as a standard to compare with in all other 
cases. 2. That under the equinoctial, the 
heat is as the sine of the sun’s declination. 
3. That in the frigid zones, where the sun 
sets not, the heat is as the circumference of a 
circle into the sine of the altitude at 6; and 
consequently that in the same latitude these 
aggregates of warmth are as the sine of the 
sun’s declination; and at the same declination 
of the sun, they are as the sines of the lati- 
tudes into tne signs of the declination. 4. 
That the equinoctial day’s heat is every where 
as the cosine of the latitude. 5. In all places 
where the sun sets, the difference between 
the summer and winter heats, when the de- 
clinations are contrary, is equal to a circle 
into the sine of the altitude at 6 in the sum- 
mer parallel; and consequently these differ- 
ences are as the sine of the latitude into or 
multiplied by the sines of declination. 6. 
From the foregoing table, it appears that the 
tropical sun under the equinoctial, has of all 
others the least force. Under the pole, it is 
greater than any other day’s heat whatever ; 
being to that of the equinoctial as 5 to 4. 
HEATH. See Erica. 
HEBENSTRETIA, a genus of the an- 
giospennia order, in. the didynamia class o£ 
gm 
plants; and in the natural method ranking 
under the 48th order, aggregatai. The ca- 
lyx is emarginated, and divided below ; the 
corolla unilabiate; the lip rising upwards, 
and quadrifid; the capsule dispermous ; the 
stamina inserted into the margin of the limb 
of the corolla. There are six species, herbs of 
the Cape. 
IlECATOMBiEON, in ancient chrono- 
logy, the first month of the Athenian year, 
consisting of thirty days, and answering to the 
latter part of our June and beginning of July* 
HECTIC, or Hectic Fever. See Me- 
dicine. 
IiEDERA, Ivy, a genus of the mono- 
gyp, ia order, in the pentandria class of plants ; 
and in the natural method giving name to 
the- 46th order, hederacai. There are five 
oblong petals; the berry is pentaspermous, 
girt by the calyx. There are six species; 
the most remarkable are: 1. The helix, or 
common ivy, which grows naturally in many 
parts of Britain ; and, where it meets with 
any support, will rise to a great height, send- 
ing out roots on every side, which strike 
into the joints of walls or the bark of trees. 
If there is no support, they trail on the 
ground, and take root all their length, so 
that they closely cover the surface, and are 
difficult to eradicate. While these stalks are 
fixed to any support, or trail upon the 
ground, they are slender and flexible; but 
when they have reached to the top of their 
support, they shorten and become woody, 
forming themselves into large bushy heads ; 
and their leaves are larger, more of an oval 
sfiape, and not divided into lobes like the 
lower leaves, so that it has a quite different 
appearance. There are two varieties of this 
species ; one with silver-striped leaves; the 
other with yellowish leaves on the tops of 
the branches ; and these are sometimes ad- 
mitted into gardens. 2. The quinquefolia, 
or Virginia creeper, is a native of all the 
northern parts of America. It was first 
brought to Europe from Canada ; and has 
been long cultivated in the Britisli gardens, 
chiefly to plant against walls or buildings to 
cover them : which these plants will do in a 
short time ; for they will shoot almost twenty 
feet in one year, and will mount up to the 
top of the highest building ; but as the leaves 
fall off in autumn, the plants make but an 
indifferent appearance in winter, and there- 
fore are proper only for such situations as 
will not admit of better plants ; for this will 
thrive in the midst of cities, and is not in- 
jured by the smoke or the closeness of the 
air. 
The roots of the ivy are used by leather- 
cutters to whet their knives upon. Apricots 
and peaches covered with ivy during the 
month of February, have been observed to 
bear fruit plentifully. The leaves have a 
nauseous taste ; Haller says, they are given 
to children in Germany, as a specific for the 
atrophy. The common people of England 
apply them to issues ; and an ointment made- 
from them is in great esteem among the 
Highlanders of Scotland as a ready cure for 
burns. The berries have a little acidity. In 
warm climates, a resinous juice exudes from 
the stalks, which is said to be a powerful re- 
solvent, and an excellent ingredient in plaa-. 
ters and ointments. Horses and sheep eat. 
the plant; goats and cows refuse it. 
