418 
Scientific Intelligence . 
noticed in the lava 6f these caverns are curious, throwing light on 
the manner in which they may have been formed, the lava ap- 
pearing like melted lead thrown into water ; the walls, in some 
places, seem to be covered with petrifactions or vegetables, and 
shrubs retaining the most perfect resemblance to their originals ; 
some specimens resembled bunches of grapes partially flattened, 
and some were like coarse salt” Webster's Account of the Island 
of St Michaels. 
47. Lithographic Prizes to be adjudged by the Society of 
Arts for Scotland. — The gentlemen who, in 18£0, associated 
themselves for the purpose of promoting the art of Lithography 
in Scotland, have transmitted the balance of their funds to the 
Society for promoting the useful arts in Scotland, for the purpose 
of forming three Prizes for improved specimens of printing, to be 
produced from lithographic designs. The particulars and condi- 
tions of the prizes will, we understand, be published soon, along 
with several other premiums to be offered by the Society of Arts. 
48. Wire Gauge recommended by the Society of Arts. — The 
Society of Arts, considering the inconvenience arising from the 
present uncertain construction of wire-gauges, are about to re- 
commend, for the adoption of artists, a new form of gauge, which 
will shew the diameter of wire in decimals of an inch. A descrip- 
tion of this instrument will appear in our next Number. 
49. Dr Charles Anderson’s Machine for measuring small 
quantities of Fluids. — 44 The want of the proper means (Dr 
Anderson remarks) of ascertaining, with precision and expedi- 
tion, small quantities of fluids in chemical experiments and phar- 
maceutical operations, has often been the subject of complaint. 
The glass measures recommended by the Colleges of Physi- 
cians of London and Edinburgh, and now in general use, are 
well fitted for measuring ounces and drachms, but they do not 
seem calculated for measuring smaller quantities with sufficient 
accuracy. 
44 The mode of ascertaining small quantities of fluids by drops, 
has been so long in use, that custom seems to have established an 
undue predilection in its favour. It must, on very little reflec- 
tion, be obvious, that this mode is very uncertain. As the size 
of the drops must vary much, depending on the viscidity of the 
fluid ; the thickness of the lip of the bottle from which they fall 
