TAA i.3.14.9

Telephone.                                                       34, Upper Hamilton Terrace,

Maida Vale 4154.                                                                              N.W.8.

                                                                        May 8th, 1933.

My dear Carter,

          A friend sent me a cutting from an American scientific

paper of a somewhat popular type giving an account of exper-

iments by Professor R.W. Wood from the point of view of the 

physicist, which showed that the gold from which the red-coo/<l>our-

-ed sequins were made contained iron. In May a year ago, Mr. j.

R. Ogden got Messrs. Johnson, Matthey & Co., the gold experts, to

make an analysis of one of the sequins and they reported tnat^sic 

the alloy contained 1.55 per cent of iron. Doubtless Mr. Ogden

sent you a copy of the analysis which fully explained the source

of the colour, known for years now to consist of nothing but

oxide of iron. My own analysis, since made with extreme care

and using a larger quantity of the alloy shows only 0.81 per

cent of iron but this is far more than enough to give the red

colour without any iron being supplied from an external source.

          I need not trouble you now with an account of all the

experiments which we have made at odd times, as you, no doubt,

will be in London shortly, if not already here.

          Dr. Plenderleith has also a lot of notes on various minerals

and materials for you but which he cannot write out owing to