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PUBLISHED AT THE OFFICE, BOY COURT, LUDGATE HILL, E.C.

AND SOLD BY ALL BOOKSELLERS.

MDCCCLXXIX.

LONDON:

PRINTED BY EDWIN JOHN DAVEY

BOY COURT, LUDGATE HILL E.C.

THE CHEMICAL NEWS.

VOLUME XXXIX.

EDITED BY WILLIAM CROOKES, F.R.S., &c.

No. 997.-JANUARY 3, 1879.

DISCUSSION OF THE WORKING HYPOTHESIS
THAT THE SO-CALLED
ELEMENTS ARE COMPOUND BODIES.*

By J. NORMAN LOCKYER, F.R.S.

IT is known to many Fellows of the Society that I have for the last four years been engaged upon the preparation of a map of the solar spectrum on a large scale, the work including a comparison of the Fraunhofer lines with those visible in the spectrum of the vapour of each of the metallic elements in the electric arc.

To give an idea of the thoroughness of the work, at all events in intention, I may state that the complete spectrum of the sun, on the scale of the working map, will be half a furlong long; that to map the metallic lines and purify the spectra in the manner which has already been described to the Society, more than 100,000 observations have been made and about two thousand photographs taken.

In some of these photographs we have vapours compared with the sun; in others vapours compared with each other; and others again have been taken to show which lines are long and which are short in the spectra.

I may state, in way of reminder, that the process of purification consisted in this :--When, for instance, an impurity of manganese was searched for in iron, if the longest line of Mn was absent, the short lines must also be absent on the hypothesis that the elements are elementary; if the longest line were present, then the impurity was traced down to the shortest line present.

The Hypothesis that the Elements are Simple Bodies does

not include all the Phenomena.

The final reduction of the photographs of all the metallic elements in the region 39-40-a reduction I began in the early part of the present year, and which has taken six months, summarised all the observations of metallic spectra compared with the Fraunhofer lines accumulated during the whole period of observation. Now this reduction has shown me that the hypothesis that identical lines in different spectra are due to impurities is not sufficient. I shall show in detail in a subsequent paper the hopeless confusion in which I have been landed. I limit myself on the present occasion to giving tables showing how the hypothesis deals with the spectra of iron and titanium.

* Paper read at the Royal Society, December 12, 1878.

We find short line coincidences between many metals the impurities of which have been eliminated or in which the freedom from mutual impurity has been demonstrated by the absence of the longest lines.

Evidences of Celestial Dissociation. '

It is five years since I first pointed out that there are many facts and many trains of thought suggested by solar and stellar physics which point to another hypothesisnamely, that the elements themselves, or at all events some of them, are compound bodies.

In a letter written to M. Dumas, December 3, 1873, and printed in the Comptes Rendus, I thus summarised a memoir which has since appeared in the Philosophical Transactions.

"Il semble que plus une étoile est chaude plus son spectre est simple, et que les éléments métalliques se font voir dans l'ordre de leurs poids atomiques.*

"Ainsi nous avons :

"1. Des étoiles très-brillantes où nous ne voyons que l'hydrogène, en quantité énorme, et le magnésium; "Des étoiles plus froides, comme notre Soleil, où nous

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"Il me semble que ces faits sont les preuves de plusieurs idées émises par vous. J'ai pensé que nous pouvions imaginer une dissociation céleste,' qui continue le travail de nos fourneaux, et que les métalloïdes sont des composés qui sont dissociés par la température solaire, pendant que les éléments métalliques monatomiques, dont les poids atomiques sont les moindres, son précisément ceux qui résistent, même à la température des étoiles les plus chaudes."

Before I proceed further, I should state that while observations of the sun have since shown that calcium should be introduced between hydrogen and magnesium for that luminary, Dr. Huggins's photographs have demo n

* This referred to the old numbers in which Mg=12. Na=23.

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