EDITORIAL OBSERVATIONS. 
39 
ON THE NEW MODE OF CHEMICAL ANALYSIS. 
Towards the close of the last volume we directed the 
attention of our readers to the new and beautiful spectrum- 
analysis process, stated to have been discovered by Pro¬ 
fessors Bunsen and KirchofF, of Heidelberg. It would, 
however, appear that to others the method had before sug¬ 
gested itself, and it had been investigated, in a more or less 
perfect manner, especially by Mr. H. Talbot in 1826, and 
Mr. Wheatstone in 1835 ; the first named having read a 
paper on the spectrum colours, at the meeting of the British 
Association for the Advancement of Science, held in Dublin 
that year. Messrs. Herschel and Brewster had also before 
experimented on coloured flames. 
In a lecture delivered by Professor Boscoe at the Royal 
Institution of Great Britain, in March last, he thus speaks 
of the advantages and delicacy of this process ; having pre¬ 
viously eulogised Messrs. Bunsen and Kirchoff, described 
their apparatus, and exhibited its capabilities by mixing 
together several metallic salts, and showing their difFerent 
colours on a screen :— 
“ In order to give some opinion of the value of this kind of analysis, I 
would tell you that the various processes which the chemist must pursue in 
in the ordinary way in order only to detect the presence—not estimate 
the quantity, but simply to detect the presence—of these five or six 
alkaline metals when they are mixed togother, occupies from two to three 
hours. And, what is more important, the results by these means are never 
absolutely certain, especially if there is only a small quantity of a substance 
present. As a contrast to this I will quote the following. M. Bunsen in 
his most interesting paper, said :—‘ A mixture of the chlorides of sodium, 
potassium, lithium, calcium, strontium, and barium, containing at most one-ten- 
thousandth part of a grain of each of these salts, was brought into the flame, 
and the spectra produced observed. At first, the bright yellow sodium line 
Naa appeared with a back ground formed by a nearly continuous pale spec¬ 
trum. As soon as this line began to fade, the exactly defined bright red 
line of lithium Lia was seen; and still further removed from the sodium line, 
the faint red potassium line K« was noticed, whilst the two barium lines 
Baa, Ba/3, with their peculiar form, became visible in the proper position. 
As the potassium, sodium, lithium, und barium salts volatilised, their spectra 
became fainter and fainter, and their peculiar bands one after the other 
vanished, until, after the lapse of a few minutes, the lines Caa, Ca/3, Sra, 
Sr/3, Sry, and Srci, became gradually visible, and, like a dissolving view, at 
last attained their characteristic distinctness, colouring, and position, and 
then after some time became pale and disappeared entirely. 5 
“ Thus we get, with absolute certainty, in half a minute, what, according 
