Was hoping to send him some positive paper, but has been unable to prepare this due to a medical problem. Did make a sheet or two today. Returns some of the specimens JH sent him but would like to keep those made by JH himself.
Was hoping to send him some positive paper, but has been unable to prepare this due to a medical problem. Did make a sheet or two today. Returns some of the specimens JH sent him but would like to keep those made by JH himself.
Is grateful for the specimens sent him. Has been carrying out a series of experiments on the Calotype process with extraordinary results, especially the crimson skies. What does he think of the idea of publishing a treatise on 'Light' considered as a chemical agent?
Has been working at [L. F.] Moser's experiments and believes he is wrong in considering latent light as the agent that produces the photographic image. Read a paper last evening on the subject, which will be printed. Has been producing images by the action of heat and electricity and proposes to call this process Thermography.
Was pleased to receive JH's letter and to read that he had really proved the existence of [invisible light?]. One of his students has produced images on copper plates by sulfur fumes. Has just seen Macedoine Melloni's memoir, which is now governed by JH's views.
Was very pleased with the specimen JH sent him; it is still in good condition. Has he read [John William] Draper's paper? Comments on some of the points. Outlines some of his own proposed experiments.
Much indebted for his paper on the influence of the solar spectrum on vegetable colors. Has a series of experiments ready that he hopes will resolve some of his own doubts. Does not like the term J. W. Draper uses for the new rays.
Sends a few samples of plates made by the cyanotype process; they are poor because the sun has not been very strong of late. Comments on this process and wishes JH would make a few experiments with his more perfect apparatus. Inclined to agree with him about the mechanism of the eye.
Has been reading JH's communication to the P.M. [on solar spectrum] and wishes to point out that RH was the first to carry out those experiments, which are recounted in the P.M. for 1840.
Sends some specimens of photographs he has made by using bichromate of potash and an acid solution of nitrate of mercury. Gives details of a luminous phenomena he has seen in the S.W. and would like an explanation of it from JH.
Enlarging on the luminous phenomena he has seen in the S.W. and giving some comments from a naval officer who had observed it.
Is grateful for the very interesting photograph; will keep the preparation secret if he discovers it. Has been trying many experiments with benzoates with curious results, but bad weather has stopped progress so has now turned to thermography to test the truth of Mr. Prater's conclusions. Comments on these.
Enclosing the specimens of photographs by different methods; comments on the methods used. Encloses a paper by Were Fox.
Enclosing specimens of his chromatype; comments on how these were produced and their characteristics. Is very busy with the Annual Exhibition of the Polytechnic Society.
Has received from the P.M. proof of an article replying to the attack of [L. F.] Moser on RH, also details of a new instrument by J. W. Draper. Would like JH's opinion on the instrument. Has had some good results with the fluorates recently.
Would like his views on a name for the combination of hydrogen and chlorine. Comments on the various theories. Has replied to [L. F.] Moser.
Thanks for his instructive letter. Comments on the terms suggested for the chemical change. Has now improved his chromatype process. Unable to continue his researches on light owing to lack of finance.
Encloses some specimens of photographs made by the use of chloride of gold and bichromate of potash. Comments on the process.
Outlines his domestic history. If JH knows of a suitable position vacant that may suit RH he would be pleased to hear of it. Cannot understand JH's lack of success with the photographic process RH uses. His own book is printed and is waiting for an engraving. Will send him a copy.
Is most grateful for JH's offer of assistance for one of his sons. Suggests the second one would be most suitable. Is certain Sir Charles Lemon, their president, would support him.
Charles Lemon has communicated to him the result of an application made by JH to Prince Albert on behalf of one of RH's children. Is deeply grateful for his assistance.