Letter from T S [Thomas Shaw] Brandreth, to Captain [Henry] Kater, Union Place, New Road He would be glad to introduce the formulae for the pendulum into his account of the sliding rule, but he asks Kater to correct any errors in his mathematics, which he presents. He gives the formulae and asks that once examined with any additions, these might be added to his letter to Captain [Basil] Hall. He sends a copy of the logometer, interleaved, so that Kater can suggest improvements to that. He concludes by saying that he has constructed a model of his 'spherical triangle', which works very well, but he must delay its completion until his return. With some pencil annotaitions, presumably by Henry Kater. [watermark 1819]