General Science. 
883 
87. On Charcoal from different Woods. — -Mr T. Griffiths has 
published, in the Quarterly Journal of Science, No. 82. p. 265. 
some interesting experiments on charcoal, which we give in the 
following Table. 
Specific 
Proportion of 
Gravity. 
Charcoal in 100 
parts of Wood, 
Lignum Vitffij 
1.342 
17.5 
Cocoas Wood, 
- 
1.336 
22.5 
Ebony, 
- . - 
1.226 
30.5 
Brazil Wood, 
1.132 
26. 
Satin Wood, 
. 
1.0T8 
20.7 
Tulip Wood, 
- 
1.070 
20.8 
King Wood, 
- 
1.069 
22. 
Botany Bay Wood, 
1*067 
28.1 
Mr Griffiths found, that charcoal from satin wood is the best 
conductor of electricity, and that from tulip wood the worst. 
The other charcoals discharge a battery with nearly the same 
effect. 
88. Mr Inne^s New Tide-Tables. — Mr George Innes of 
Aberdeen, to whom we are indebted for the calculation of the 
Celestial Phenomena, has published for 1825 an useful little 
work, entitled, New Tide Tables, shewing at sight the true time 
of high-water at Aberdeen and London, the sun’s declination 
every day at noon, the eclipses, and the moon’s age, with a 
Table, by which the true time of high-water at the principal 
ports along the coasts of Great Britain may be known. 
89. Mr GalhraitlCs Stereotyped Mathematical Tables.'^T\m 
work, from the pen of Mr William Galbraith, A. M., Lecturer 
on Mathematics, Edinburgh, contains improved Tables of 
Logarithms, of Numbers, of Logarithmic Sines, Tangents, and 
Secants ; together with other Tables, useful in Practical Mathe- 
matics, Astronomy, Navigation, Engineering, and Business. 
They are preceded by a copious Introduction, embracing their 
explanation, and Rules and Formulae of their application ; with 
a collection of appropriate examples for solution. From a spe- 
cimen of this work which we have seen, we have no doubt but 
that it will do great credit to the author. 
40. Engraving of a Brazilian ^-Naturalists and tra- 
vellers have essayed to make known to us the wild forestsof South 
America ; but neither the comprehensive descriptions of bota- 
