Much of the Author’s theory seems to depend on the assumed transparency of flame. See p 77.² But the theory of exchanges (supported by an immense weight of evidence) so far from proving this as the Author states, really asserts just the contrary.³ No thickness of flame at a given temp^re. can radiate more than a single lamp black surface at the same temp^re. w^d. do. The view in the book is entirely inconsistent with the facts of spectrum analysis.⁴ This being so, the argument from dissociation w^d. tend to shew that the Sun’s heat cannot possibly be due to burning hydrogen, for in order that the total heat radiated s^d. be as great as we find it, the solar temperature must be so high that hydrogen would not burn.

Many of the minor points brought forward seem to be established. Thomson⁵ I believe agrees that there is no particular limit to the atmosphere, tho the idea that the interior of the Sun could be cool below the flaming atmosphere is shewn to be in the highest degree improbable.⁶

I am not competent to judge with decision on the astronomical parts, but the Author does not seem to be acquainted with Thomson’s papers, nor to understand the bearing on the questions he discusses of the laws of Thermodynamics w^h. are almost universally admitted.⁷