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•with borax it gives a glassy bead, clear and colourless, both 
hot and cold, and no trace of absorption bands can be seen 
in the spectrum ; but, if the borax bead be saturated at a 
high temperature, and flamed, so that it may be filled with 
crystals of borate of jargonia, the spectrum shows four 
distinct absorption bands, unlike those due to any other 
known substance. 
New Applications of the Microscope to Blow-pipe Che- 
mistry. — Of these there are two chief divisions. In one 
method the substance is fused with borax or microcosmic salt, 
so as to give a clear bead, and the spectrum is examined by 
means of the spectrum eye-piece. In the other method the 
saturated borax bead is kept hot over the lamp, so that crys- 
tals may be deposited in it. By using a microscope many 
elements may then be easily distinguished by the form of the 
crystals, which are often of extreme beauty. When, however, 
much mixed, or combined with silica or other acids, as in 
natural minerals, it is often requisite to add various re-agents, 
as phosphate of soda, microcosmic salt, boric, tungstic, 
molybdic, and titanic acids. These give rise to characteristic 
crystalline deposits; and we may thus distinguish lime, mag- 
nesia, baryta, and strontia, even when combined with silica; 
and can detect magnesia when mixed with several times its 
weight of lime in impure limestone, &c. 
Examples of this method. — 1. Sphene melted with borax 
does not deposit crystals; but the addition of boric acid sets 
free the titanic acid, easily recognised by the form of the 
crystals. Diluting the bead with more borax, so as to retain 
the titanic acid in solution, phosphate of soda causes the 
deposit of crystals of phosphate of lime. 
2. Fergusonite, from Greenland, shows the spectrum of 
didymium, and from Ytterbv that of erbium. When fused 
with borax it deposits crystals of columbic acid ; and after 
diluting with borax to prevent this, the addition of phosphate 
of soda produces crystals of phosphate of yttria. 
3. Gadolinite from Ytterby melted with borax gives a 
spectrum indicating the presence of didymium and erbium ; 
and when kept hot it deposits the characteristic crystals of 
borate of yttria. 
Embryology. — Germination of the Spores of Varicellaria. 
By Dr. W. Nylander. Annals of Natural History (Decem- 
ber), translated by the Rev. W. A. Leighton. — The spores of 
Varicellaria, which are the largest spores of all lichens, were 
placed by Nylander in a humid atmosphere, and — as seen by 
De Bary and others — were soon covered with slender circum- 
radiant filaments. In the course of a month or so these 
