Unpublished paper, 'On some peculiar modifications of the force of cohesion, with reference to the forms and structure of clouds, films and membranes' by William Addison Addison summarises twelve experiments on the force of cohesion. He finds that transparent liquid streams are visible when vapours or fluids mingle with one another and when solids are dissolving in a fluid. He notes that opaque deposits, which look like clouds, form on those streams, rendering visible the lines of junction of two fluid or gaseous surfaces. Subject: Chemistry / Fluid mechanics Received 29 May 1845. Communicated by Samuel Hunter Christie. Whilst the Royal Society declined to publish this paper in full, an abstract of the paper was published in volume 5 of Abstracts of the Papers Printed in the Philosophical Transactions of the Royal Society of London [later Proceedings of the Royal Society] as 'On some peculiar modifications of the Force of Cohesion, with reference to the forms and structure of Clouds, Films and Membranes'. May 1845