Showing 21–40 of 76 items
The Sir John Herschel Collection
The preparation of the print Calendar of the Correspondence of Sir John Herschel (Michael J. Crowe ed., David R. Dyck and James J. Kevin assoc. eds, Cambridge, England: Cambridge Univ. Press, 1998, viii + 828 pp) which was funded by the National Science Foundation, took ten years. It was accomplished by a team of seventeen professors, visiting scholars, graduate students, advanced undergraduates, and staff working at the University of Notre Dame.
The first online version of Calendar was created in 2009 by Dr Marvin Bolt and Steven Lucy, working at the Webster Institute of the Adler Planetarium, and it is that data that has now been reformatted for incorporation into Ɛpsilon.
Further information about Herschel, his correspondence, and the editorial method is available online here: http://historydb.adlerplanetarium.org/herschel/?p=intro
No texts of Herschel’s letters are currently available through Ɛpsilon.
Has performed some Newton's rings interference experiments. Asks whether such experiments have already been communicated to the R.S.L.
Trying to understand David Brewster's results on absorption of light in gaseous state, and the dark lines in solar spectrum, the cause of which he misunderstands.
About plant seeds sent by JH from the Cape, WT having sent him some Mexican seeds in return. Halley's Comet only clearly seen on two nights.
Writing to welcome JH home from the Cape.
About Cape bulbs and seeds, the new travel by railway from Slough to London, and concern about interest in animal magnetism.
Thanks for more Cape bulbs.
Transmits a message from J. B. Biot, comments on the Daguerreotype, although WT has not tried it.
Comments on many different processes in photography. Still has not tried the Daguerreotype, although WT has had the equipment for a considerable time.
Will give a paper on fixing the image formed by the camera obscura to R.S.L. and wants to review it with JH first.
JH is indisposed, so WT will come to Slough to review paper [see WT's 1839-1-25]. Asks JH about appropriate curve on lenses for camera obscura for 2-foot focus.
Has received urgent request from Athenaeum to allow them to publish paper on 'Photogenic Drawing' before it is read to R.S.L. in light of announcement of the 'Parisian invention.'
Wants to withhold description of 'developing' process until it is perfected to obviate others using it. Also refers to second process to make 'positive' and 'negative.'
Some comments on JH's light and photography experiments, especially effects of different kinds of glass and fixing with ferrocyanate.
Describes mediocre results obtained using ferrocyanate of potash for fixing image. Mentions some other methods, including his favorite, common salt. Asks JH to keep these secret.
More about paper being published in both the R.S.P.T. and Athenaeum.
Finally had success washing with ferrocyanate. Wants to present note of 'his' processes to R.S.L. and so to the world.
Wishes to communicate to J. B. Biot, and so to Academie des sciences, JH's two 'beautiful' fixing methods, by hyposulfite and ferrocyanate.
Questions JH's intent to display 'photogenic drawings' to R.S.L.
Enlarges upon his method of using salt as photographic fixer; then asks JH to explain the chemistry thereof. Has tried Louis Daguerre's fixing process without success.
Further chemicals used for fixing, including bromide potash.