CD's urine sample was probably alkaline when passed. The deposit was phosphate of lime. Prescribes a new antacid and continuation of podophyllin. He can judge CD's state as described by his letter.
8 Harley S
My dear Sir
I had the sediment examined: it was phosphate of Lime— I suppose the urine was alkaline when passed. I think it would be well to try some other antacid than chalk. ie to omit that for a time— I enclose a prescription for a combination of antacids— I would also advise an increase in the Lime & the omission of the Colchicum— Continue the Podophylin—
I do not think any advantage would be derived from a visit— I have now seen you often enough to judge well of your state as described by letter—
Yours very sincerely | W
Charles Darwin Esq
- f1 4589.f1Emma Darwin may have taken this sample to Jenner when she visited him in London on 5 July 1864; his most recent visit to Down was on 22 May 1864 (see `Journal' (Correspondence vol. 12, Appendix II)).
- f2 4589.f2Emma Darwin's diary (DAR 242) records that CD `left off chalk' on 16 August 1864. Jenner had prescribed a combination of antacids, including chalk, limewater, magnesia, and carbonate of ammonia, when he began treating CD in March (see letter to J. D. Hooker, 13 April  and n. 6, and letter from Emma Darwin to W. D. Fox, [6 May 1864]).
- f3 4589.f3The enclosed prescription has not been found; however, Emma Darwin's diary (DAR 242) for 17 August records `began bismuth &c.' Bismuth was used to treat gastric acidity and dyspepsia (see Beasley 1865, pp. 131--4, and Royle and Headland 1865, pp. 185--6). CD's new prescription for antacids may also have included potash (see letter from William Jenner, 9 November 1864 and n. 4).
- f4 4589.f4Preparations made from the seed and root of Colchicum autumnale were used as a purgative in the treatment of gout (see Beasley 1865, pp. 185--9, and Royle and Headland 1865, pp. 636--8). Emma Darwin's diary (DAR 242) records that CD began taking colchicum on 24 March 1864. See also letter from William Jenner to [W. W. Baxter?], [after 7 May 1864?].
- f5 4589.f5For CD's use of podophyllin, see letter from E. A. Darwin to Emma Darwin, 30 [March 1864?] and n. 4, and letter from William Jenner to [W. W. Baxter?], [after 7 May 1864?].
- f6 4589.f6Jenner had visited Down on 20 March, 10 April, and 22 May 1864 (Emma Darwin's diary (DAR 242)).