-233 
HOROLOGY. 
compenfation, of reducing and equalifmg friflion, 8 cc. 
will never produce good fnachihes for meafuring time ; 
and, even Ihould he copy the heft machines made by others, 
he will never fucceed. Our intention is therefore to de- 
fcribe briefly the general principles of common clocks and 
watches, and afterwards to detail more at large the lateft 
improvements.—We muft however firft fpeak of the ori¬ 
gin and progrefs of this curious and ufeful art. 
GENERAL HISTORY OF HOROlOGY. 
The term horologium occurs very early in different parts 
of .Europe ; but as this word, in old times, fignified a 
dial as well as a clock, nothing decilive can be inferred 
from it, unlefs it can be fhown, by concomitant circum- 
Jtances or expreffions, that ic relates to a clock rather than 
to a dial. Dante feems to have been the firft author who 
has introduced the mention of an orologio that ftruck 
the hour, and which confequently cannot be a dial, in 
the following lines: 
indi come horologio che ne chiami, 
Nel bora che la fpofa d'Idio furge, 
Amattinar lo fpofo, perche l’ami. Paradifo, x. 30. 
-Like folemn chimes at noon of night. 
That cal! the fpoufe of God her faith to plight, 
And love for love with fervent heart return; 
When found to found refponfwe vibrates clear ; &c. 
Dante was born in 1265, and died in 1321, aged fifty- 
feven; ftriking-clocks therefore could not have been very 
uncommon in Italy at the latter end of the thirteenth 
centuiy or the beginning of the fourteenth. But the ufe 
of clocks was not confined to Italy at this period; for we 
had an artift in England about the lame time, who fur- 
hilhed the famous clock-houfe near Weftminfter-hall, with 
a clock to be heard by the courts of law, out of a fine im- 
poled on the chief juftice of the -King’s Bench, in the fix- 
teenth year of Edward I. or in I2S8. We find that this 
clock was confidered, during the reign of Henry VI. to 
be of fueh confequence, that the king gave the keeping 
of it, with the appurtenances, to William Warby, dean 
of St. Stephen’s, together with the pay of fixpence per 
diem, to be received at the Exchequer. See Stowe’s Wel’c- 
minfter, ii. 55. The clock at St. Mary’s, Oxford, was alio 
furnilhed in 1523, out of fines impofed on the ftudents of 
the univerlity. 
Weidler and Chambers are doubtlefs in a miftake when 
they place the invention of automatous clocks about the 
end of the fifteenth or beginning of the fixteenth century. 
The latter fays, “ It is certain that the art of conftrufting 
clocks, fuch as thofe now in ufe, was firft invented or at 
leaft revived in Germany about two hundred years ago.” 
The fame account is given by Weidler, whom Chambers 
perhaps copied. But this opinion is fo apparently falfe 
in regard to the time, that one cannot alfent to it; nor is 
it even probable in regard to the country, though it muft 
be allowed that the art of clock-making flourilhed veiy 
much in Germany, particularly at Nuremberg, about the 
beginning of the fixteenth century. Beckman’s Hilt, of 
Inventions, vol. i. 
As thefe two authors make the invention of clocks too 
modern, others, on the contrary, carry it back to a period 
too early. A certain writer pretends to have found men¬ 
tion made of a clock in the third century. In fupport of 
this affertion he refers to the Acts of St. Sebaftia’n the Mar¬ 
tyr ; but, whatever this nipchine might have been, it was 
of no ufe to others, or to pofterity; it was devoutly broken 
to pieces by St. Stephen and St. Polycarp, becaufe it ex¬ 
hibited the motions of the planets, which were called by 
heathen names; fo that, even allowing it to have b'een a 
clock, the knowledge of it muft have been loft. We find, 
alfo, that Bernardus Saccus afcribes the invention of clocks 
to Boethius, in the fifth century; but Bernardus feems to 
have forgotten what he quoted a little before from Caffio- 
dorus, refpefHng the clock of Boethius, that it determined 
the hours guttis aquarum, “ by drops of water.” It muft, 
therefore, have been a wat^r-clock, and not a clock moved 
by wheels and weights. The fame Cafliodorus had pro¬ 
vided his monks at the monaftery of St. Andiol, in Lan¬ 
guedoc, with machines of the like kind. 
We come now to the feventh century. In Du Frefne’s 
Lexicon we find the word Index, which is explained to be the 
index or hand of a clock, or the final! bell which announces 
the hours by its found; and this opinion is adopted by 
Muratori. Du Frefne quotes in fupport of his affertion 
a monkilh work called Regula Magiftri, the author of 
which is not certainly known, but which Mabillon afferts 
to have been written before the year 700. But Du Frefne 
might have perceived that a clock is not here alluded to, 
had he quoted the whole paffage from the fifty-fifth chap¬ 
ter. That machine which was fent as a prefent to Charle¬ 
magne by the king of Perfia, in the year 807, is fuppofed 
alfo to have been a clock like thofe ufed at prefent; and, 
if we follow the Chronicon Turonenfe, we may eafily fail 
into the fame opinion. The defcription of it however to 
be found in Annales Francorum, afcrihed to Eginhard, 
fliows clearly that it was far different from our clocks : it 
was evidently a water-clock, furnilhed with fome inge¬ 
nious mechanifm, but having nothing in common with the 
wheel-work of clocks. 
That even thefe water-clocks, however, were then fcarce, 
as well as in the following centuries, we have reafon to 
conclude from their being fo little fpoken of in the writings 
of-thofe periods. In the ancient cuftoms of the monaftery 
of St. Viton, at Werden, written as is faid in the tenth 
century, no,mention of them occurs; andjthe monks re¬ 
gulated their prayers by the crowing of the cock; for it 
is faid: Cum lucem ales nunciaverit , dabuntur omnia figna in 
refurreElionc Domini nofri, &c. We find as little mention 
of them in the eleventh century, even in paffages where 
they could not have been omitted had they been knov/n. 
Some afcribe the invention of our modern clocks to 
Gerbert, vdro, in the tenth centuiy, was raifed to the pon¬ 
tifical chair at Rome, under the name of Sylvefter II. and 
who was reckoned, to be the firft mathematician and aftro- 
nomer of his time. This opinion, however, is fupported 
only by mere conjecture, and appears to be falfe from the 
account of Dithmar, in which no mention is made of wheels 
or weights; fo that this feems to have been a fun-dial, 
which Gerbert fixed up by obferving the pole-ftar. It ap¬ 
pears, indeed, that Gerbert w r as acquainted with no other 
kind of clock; for thole who fpeak of his book in which 
he explains the method of conftrufting dials for various 
latitudes, produce no farther proofs. Some, according 
to the teftimony of Kircher, confider it to have been a 
portable dial, which Ihowed the hour when properly fet 
by the help of a needle touched by a magnet; but even 
this opinion is not warranted by the vrords of Dithmar. 
The anonymous author of the Life of William abbot of 
Hirlhau, wdio lived in the eleventh century, and who w’as 
a very learned man for his time, fays, Naturale horologium 
ad exemplum caeleflis hcemifpherii excogitaffe. Though this 
paffage is fo Ihort, that no idea can be formed from it of 
the conftruftion of the machine, it is evident that it al¬ 
ludes neither to a fun-dial nor to a water-clock, but to 
fome piece of mechanifm which pointed out the hours, 
and exhibited the motion of the earth and other planets. 
As more frequent mention of horologia occurs afterwards, 
and as, in fpeaking of them, expreffions-are uled which 
cannot be applied to fun-dials or water-clocks, we are in¬ 
duced to think that the invention of our deck' belongs 
to this period. In the Conftitutiones Hirfeugienfes, or 
Gengebacdnfes, of the fame William, it is find :f the 
facriftan, cum horologium dirigere ct ordinate, in the like 
manner Bernardus Monachus, a writer of the ftm , cent 
tury, in the Ancient Cuftoms of the Monaftery of K Vic¬ 
tor, at Paris, faysj that the regifter, the facrift's .compa¬ 
nion, ought !t horas canon icas nocte et die ad divinum 
ceiebrandurn cullodire, figna pullare, horologium temper are." 
The unequal hours then in ufe rendered this regulating 
Of the horologia neceftary. ■-Th'e-days and the nights- con¬ 
futed 
