SCIENTIFIC SUMMARY. 
333 
states that it is well known that it requires some tact to bend a tube with 
an even curve and without collapsing its sides, and many chemists never do 
succeed in bending them skilfully. Although having no particular skill in 
this matter, he never fails to bend them perfectly satisfactorily, by using a 
flame different from the one usually employed ; the flame is one given by 
the Bunsen burner described in his article on alkali determination in sili- 
cates (see Chemical News, vol. xxiii., p. 235). The burner is very commonly 
used now in all laboratories, where the extremity of the burner is flattened 
out so as to give a short and thin but broad flame, something like the flame 
of an ordinary gas-burner. The tube is placed in this flame and turned 
round and round, until a good heat is given to the tube ; it is then with- 
drawn from the flame and bent, when it does so with a perfect curve and 
no collapse of the sides of the tube. Of course this is only intended for the 
smaller tubes, but a tube of 1 centimetre and more can be thus bent very 
readily. 
Spectra of Manganese in Blowpipe Beads . — Manganese may be easily 
detected in this manner according to Mr. Charles Horner ( Chemical Nexus', 
March 22). The following is the best way of preparing the beads and ex- 
amining their spectra. Sufficient chlorate of potash should be volatilised in 
the loop of platinum wire to form a bead about the size of a pin’s head, 
then take up the merest trace of the oxide and fuse it ; next add enough 
chlorate to fill the loop, and very gently flame the bead for a few seconds 
and withdraw, when it crystallises a delicate pink colour. In adding the 
second portion of chlorate care must be observed not to volatilise the salt, 
and the best result is when the bead does not much exceed the thickness of 
the wire. If after adding the second portion we volatilise the chlorate, we 
immediately obtain a greenish-coloured bead of manganate of potash, and 
more transparent than the pink bead. In order to see the spectra of these 
beads, they should be examined by the spectrum microscope and strongly 
illuminated. The pink bead exhibits several absorption-bands more or less 
definite according to the amount of manganese present. The three most 
distinct bands, however, lie between D and b, and may be seen when the 
bead is scarcely coloured. This spectrum very closely resembles that given 
by the crystals of perchlorate coloured by permanganate of potash, but the 
bands are slightly more refrangible in the former. The green bead gives a 
spectrum of two bands, one broad band covering the sodium line, and a very 
narrow band in the orange ray. This spectrum test is most useful in the 
examination of minerals, for although the pink colour is sometimes disguised 
by the presence of other substances, as in rhodonite, which communicates a 
yellowish tint to the bead, yet the three principal absorption-bands are 
plainly visible. 
ZOOLOGY AND COMPARATIVE ANATOMY. 
Zoological Nomenclature. — This subject has excited considerable attention 
in the United States. u Silliman’s American Journal,” May 1872, contains an 
important review of Mr. Lyman’s recent and somewhat novel opinions on 
the subject. We of course cannot enter on so long a question. We may, 
however, refer the reader to Mr. Lyman’s work, “ Illustrated Catalogue of the 
