1828.] 
is found to produce effects very much sur- 
passing those of a shot of equal weight 
thrown from acannon, and this is accounted 
‘for by supposing that the force of recoil, 
which in a cannon is so great as to throw it 
‘a considerable distance backwards, is added 
in the new form of shot to the usual quantity 
of projectile force. The experiments made 
with shot weighing up to twenty-five pounds, 
were successful beth as to force and direc- 
tion, and the advantage gained as te light- 
ness in the apparatus is extraordinary. 
Discovery of a MS. of Ediesi.—A dis- 
covery has been made in the royal library 
of Paris, of a manuscript of the Geography 
of Ediesi. Hitherto only an abridgment of 
this Arabian geographer has been known, 
than which, the work in question is five 
times more voluminous. Ediesi wrote at 
Almeira, of which he was a native, about 
the year 734 of the Hegira (1345 of our 
ra). His Geography affords some ex- 
-tremely curious details on the state of places 
at the time he wrote. Many extracts have 
been made from it, but fragments only 
have come down to us. The new MS. af- 
fords many different readings of names, 
which haye not been always correctly writ- 
ten in the passages which have as yet ap- 
peared ; indeed, the errors have been mul- 
tiplied with the number of copies, so that 
the present MS., more than 200 years old, 
will in this respect afford some valuable in- 
formation. 
Waste of Food.—From an experiment 
recently made of the loss sustained by the 
usual process of cooking rice, and throwing 
away the water in which it has been boiled, 
it has been ascertained that about one- 
thirtieth part of the rice is lost: in other 
words, food enough for one day in every 
month is habitually thrown away; and a 
«country which, like Bengal, maintains near- 
ly 30,000,000 of people fed with rice, might 
nourish one million more from the same 
tillage and produce, which now support a 
Jess number. 
Improved Mariner’s Compass.—An im- 
provement in the disposal and hanging of 
the mariner’s compass on shipboard has been 
made in America. It dispenses with the 
use of the binnacle; a hole is cut in the 
deck, within this hole the compass box is 
placed, and at top covered by a very thick 
glass ; the bottom of the box is also made 
of glass, the compass card is made semi- 
transparent, and the whole lighted from be- 
low. By these means the use of a tell-tale 
is dispensed with, and the compass rendered 
much more secure than in its former posi- 
tion, as it is as firm as the deck. 
- Brazilian Tea.—The tea plant has with- 
in the last few years been cultivated in 
Brazil on a very large scale, and with great 
success. It was originally brought from 
China about the year 1816, when a number 
‘of Chinese, accustomed to its cultivation 
‘and preparation, were at the same time con- 
veyed to Rio de Janeiro, for the purpose of 
Varieties. 
317 
naturalizing it. It was at first planted at 
the royal estate at Santa Cruz, formerly be- 
longing to the Jesuits, and, eventually, it 
was spread to several of the provinces. In 
that of Saint Paul, where the soil and cli- 
mate have been found peculiarly congenial, 
the plantations are on an extensive scale; 
and the Brazilians are said already to grow 
‘sufficient for their own consumption. In 
five years it is expected they will be able 
to export a considerable quantity. Some 
scientific persons in London, who have been 
furnished with samples of Brazilian tea, 
have found it on infusion stronger than that 
of China, usually drank, which may per- 
haps be -owing to its being of last year’s 
growth, while the Chinese tea consumed in 
England is generally three or four years 
old. 
Solution of adfected Quadratic Equations. 
—Whatever be the original form of aqua- 
diatic equation, it must always be reduced to 
this formula of three terms: v2--pa-+-g—=o, 
in which p is the sum of the roots, and ¢ is 
their product. Now having their sum, and 
substituting d for their difference, we have, 
by a well-known theorem, the two roots in 
their expression: --p-+-d 
2 
sign of p is always contrary to what it is in 
the above formula. Also we have pdy, 
2 
p—2 : , 
5 =+ 9. In which equation d=+4 
3 in which the 
— > 4 
WV p® 44g: here the sign of g is con- 
trary to what is in the formula. Hence, 
es — fio 
Fret¢ +eptv pty 
See drew eev@e anda 
= 
$ an expres- 
sion containing the two roots of the given 
equation in terms of known quantities. 
Archeology.—In the village of Voor- 
burg, near the Hague, there is a country- 
house, called Arensburg, where the ruins of 
a Roman edifice have been discovered, of 
which the bricks bear the marks of the 
10th, 16th, and 30th legions, as well as those 
of the army of Lower Germany ; numerous 
fragments of wine and oil jars, furniture, 
ornaments, &c. have been found. The 
structure appears to resemble the Roman 
villas which have been met with in England. 
It is certain that the Roman fortress at the 
mouth of the Rhine was swallowed up by the 
sea, and which was commonly called Het 
Huiste Britten, did not at all resemble the 
edifice at Voorburg, but was much smaller. 
The remains are very spacious, and extend 
beyond the domain above mentioned. M. 
Renvens, professor of Archeology at Ley- 
den, has the charge of superintending the 
excavations. 
Human Salamander.—A Spaniard, by 
name Francisco Martinez, has been asto- 
nishing the Parisians, as much by his as- 
sumed title of an incombustible man, as by 
exposing himself to a degree of heat thirty 
