1802. ] New Patents 
and uncommon, the chords and difchords, 
with their revolutions, and the moft ufe- 
ful rules of thorough bafs. 
The box refembles in its form the fize 
and figure of a back-gammon_ table. 
When “opened, it prefents on the face of 
one of its halves, at each end, two mufi- 
cal faves or fyftems of five -lines each. 
Thefe ftaves have holes to receive pins of 
turned ivory and_,wood, reprefenting the 
fharps and flats which belong to the differ 
ent. keys. . Under the flaves are two 
drawers ; one of which contains dice, 
pins, &c. to be ufed in. playing with 
iharps; the other, the dice, pins, &c. 
which are to be ufed in playing with flats. 
Between the-drawers, and under the fame 
fide of the opened box, are lodged two 
dice-boxes to be ufed in the game. 
Theother face of the,table.is of one 
piece. It has, at each end, a delineation 
of the clavier or finger-touches of :a pia- 
no-forte; and, in every, one of thefe, a 
final! hole. Over thefe are two mufical 
ftaves, on which all the notes of the natu- 
yal fcale are written in crochets. Each 
crochet has, in its head, a hole to receive 
a pin: and immediately below each is 
another hole to receive a pin with the 
mark on its head of @ fharp, flat, or na- 
tural. A drawer below contains the ap- 
paratus appropriated to this table, confilt- 
ing of dice, counters, &c. particularly 
marked for the intended game.. 
With this apparatus and thefe tables, 
a feries of games are played, the chances 
of which condué the players through fo 
many improving exercifes in the know- 
ledge of the fundamental principles of 
mnufical compofi ition. 
— 
MR. J. B. DENIZE’S PATENT for a par- 
ticular CEMENT. ‘ 
On the 16th of July laft, Mr. Denize 
enrolled in the proper office of record, a 
fpecification of an invention of a particu- 
lar cement, for the exclufive ufe of which, 
during a wonted time, he has obtained 
the protection of Letters Patent from his 
Majefty. 
The principle on which the grand pe- 
culiarity of his invention is founded, is 
{imply this, thar a greater quantity of 
viicid matter than is commonly employed, 
ought to enter into the compofition of ce- 
ment, to render it fufficiently adhefive. 
Mr. Denize ufes, in the preparation of 
his cement, two different kinds of matters; 
jixed fubfiances, and vilcid matters capa- 
ble of Jiquefaflion. The fixed matters 
are, 4. Metallic, and particularly ferru- 
ginous fcorize, fcums, droffes, file-duft, 
and other remains, luch.as may be pro- 
cured from forges» 2. Metallic calces 
or oxides of all forts; any of the native 
oxides of irom; volcanic athes, lava, 
pozzolana, or: pumice-flone ; afhes of all 
forts which can be procured by the inci~ 
neration of pit-coal, charcoal, or any ve- 
getable body; any -of the fimple earths, 
as filex, alumina, Jime, magnefia;. barytes, 
&c. 3. Pit-coal as nearly as poflible of 
thecharaéter of that which is known in 
England by the name of Cannel-caal. 
4. A proportion of glafs or flint-ftone. 
Charcoal and foot, glafs-flint im any 
form, potter’s. earth, brick, tile, ~flate; 
clay, marle, gravel, fandftone, lime, plaf» 
ter, fand, fhells of all forts, Mr. Denize 
has alfo Weeds as fixed matters, in. the’ 
compofition of his cement. But, he has 
found, that if they be ufed either exclu- 
fively,.or in too great a proportion, the 
cement cannot be made with them. 
The vifcid matters, capable of liqueface 
tion, which he employs, are thefe. Sul- 
phur (not precifely of this character) in 
flour; bitumen extracted from pit-ceal, 
or petrol, mineral pitch, naphtha, or af- 
phaltos; tallow-pitch, white-rofin, pitchs 
tar, or any fimilar refinous extract from: 
vegetables; the mucilage procured’ by 
the decoétion of linfeed, to the confiftency 
of about twice the thicknefs of the white 
of an egg; or, inftead of this laft matter, 
any fimilar oily and mucilaginous fub- 
fiance, prepared from matters, animal or 
vegetable. 
He prepares the fixed matters for mix- 
ture in his cement, by cleaning the voi- 
canic fubftances or others analogous to 
them from all extraneous mixture, reduc- 
ing them to a powder, of the finenefs of 
the fineft white afhes, calcining them in a 
furnace, if they be not already in a ftate 
of fufficient calcination, wafhing them im 
an alkaline lye, then thoroughly drying; 
and laftly, fifting them. ‘The pit-coal, 
glafs, and flint-ftone, are to be reduced, to 
the fame fine pulverization as the other 
matters, and to be fifted. The wifcid 
matters are next to be feparately prepared. 
In this manipulation he takes flour. of 
fulphur, in che proportion of one-eighth 
of the whole-bulk of cement intended to 
be. made. With this he mixes bitumen’ 
from pit-coal, to the amount of about 
one-third, of the quantity of the fulphar. 
The mixture is then expofed to the heat 
of a very moderate fire, till bubbles begin 
to rife on its furface ; and it appears to 
be completely diffolved. While: on the 
fire, it is conftantly ftirred: continue the 
ftirring for fome time,after you remove it 
the fre; and during this agitationy add: 
to the liquid mixture, one-third of: black 
aa: UN aa pitch, 
lately Enrolled, 
