Paper, 'On the double tangents of a curve of the fourth order' by A [Arthur] Cayley Subject: Mathematics Published in Philosophical Transactions as 'On the double tangents of a curve of the fourth order'. Received by the Royal Society on 30 May 1861. Read 20 June 1861. Abstract published in Abstracts of the Papers Printed in the Philosophical Transactions of the Royal Society of London [later Proceedings of the Royal Society of London], Volume 11, 1862. [1861]