32 On Carbon and Hydrocarbon in the Modern Spectroscope. 



had previously called the carbohydrogen-spectrum, and declared 

 it to be the spectrum of the glowing and incandescent vapour 

 of carbon ; wherefore the earlier announced truth of the Scottish 

 professor was extinguished, and the error of the Royal Society 

 became so fashionable in London circles, that every one began 

 to talk thenceforth of that particular spectrum as the undoubted 

 spectrum of " carbon." 



Hence, too, when so admirable an observer and inimitable a 

 spectroscopist as Dr. Huggins found the spectra of two small 

 comets resolvable into bands somewhat similar to those of the 

 carbohydrogen, he boldly called them the bands of the carbon- 

 spectrum ; and it was approved by the secret committee of the 

 Royal Society and printed in their Philosophical Transactions 

 in 1868. 



But Dr. Huggins, as a good practical experimenter as well as 

 astronomical observer, knew full well the impossibility of the 

 spectrum of carbon being seen without an almost supernatural 

 degree of heat being applied to it ; how, therefore, did he show 

 that such heat existed in the ultra-faint comets which he had 

 spectroscoped ? 



The method is worthy of the gravest note, as showing (from 

 its being actually printed with honour in the Philosophical 

 Transactions) what equivocal conclusions will pass the secret 

 committees of the Royal Society when they correspond with the 

 prejudices of some person or persons behind the scenes there; 

 though those unknown powers do occasionally act as very dra- 

 gons in keeping out any salutary doubt expressed on a favoured 

 topic. For this was the heat-agency announced, viz. : — 



That " some comets have approached the sun sufficiently near 

 to acquire a temperature high enough to convert even carbon 

 into vapour." 



Not the comets, be it remarked, that were actually the sub- 

 ject of these observations, but some other comets of a totally 

 different form of orbit and infinitely nearer approach to the sun. 



Of such totally different comets, too, the only one that was 

 mentioned is the unprecedented comet of 1843, which approached 

 the sun's surface within a distance of a seventh part of the solar 

 radius. But even there, no proof is attempted or demonstration 

 given either of what spectrum that comet would have shown if any 

 one had spectroscoped it (for no one did), or that its temperature 

 was high enough to volatilize carbon efficiently for the spectro- 

 scope — only that Sir John Herschel had said that the heat the 

 comet had experienced must have been 47,000 times as intense 

 as what the earth receives from the sun. But as that still more 

 eminent authority in solar spectroscopy, Professor Angstrom, 

 has declared since then for there not being heat enough even in 



