Plate, figure 12 showing curve of caustic with cusp at infinity on x-axis by Arthur Cayley Figure 12 showing the curve of a caustic with a cusp at infinity on the x-axis. Subject: Mathematics Published in Philosophical Transactions as 'A memoir upon caustics'. Written by Cayley at 2 Stone Buildings [Lincoln's Inn, London]. Received by the Royal Society on 1 May 1856. Read 8 May 1856. [1856]