Unpublished paper, 'Estimate of the force of explosion of coal gas' by unknown author Unpublished paper regarding the calculation of the force of the exploding compound by using the analogy of other similar effects. Refers to paper by Dr [William] Henry in Philosophical Transactions of 1808 ('Description of an apparatus for the analysis of the compound inflammable gases by slow combustion; with experiments on the gas from coal, explaining application') on his findings that good coal gas requires about twice its bulk of oxygen gas for its combustion. A faint pencil inscription above title reads 'Anon', but below a very faint inscription [erased?] reads 'Read before the Committee of the A[...] in the year' and 'by Mr [illegible]. 'Mr Young' in top left corner is struck out, possibly referring to Thomas Young. A few marginal annotations in pencil throughout. Subject: Chemistry [early 19th century]