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16 
March 10th 1843
Prepared phosphorous paper by first moisting or rather wetting the paper with gum water, and then sprinkling by means of a sieve, the powdered sulphuret of lime over the wet surface.
  The sulphuret of lime was prepared by
first calcing a quantity of powdered oyster shells for at least an hour in an intense fire, then mixing with this powder 1/3 part by weight of flower of sulphur, and lastly heating the mixture for an hour in a crucible. This preparation is very sensible to the electrical emination. With a discharge from a single jar, the spark appearing between the points of two blunt wires, the phosphorous became luminous when placed at the distance of 54 inches from the spark.

  I observed one fact which may lead to some interesting results, namely that the emination which produces the phosphoro[[hole in page]] light looses
more by being reflected from a surface
of glass or of metal, than ordinary light does [[diagram in margin]] under the same circumstances. The phosphorous was so placed as that the direct emination could not reach it The arrangement was as shown in 
the margin [[underlined]] a [[/underlined]] is the mirror, [[underlined]] c [[/underlined]] the spark, [[underlined]] b [[/underlined]] the phosphoring, [[underlined]] s [[/underlined]] a screen. The light was more feeble from the mirror than from the direct radiation, although in the case of the latter, the phosphorous was placed at 4 times the distance
  I at first thought this was peculiar to the glass but found the same result with a metallic mirror

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[[overwrite]] Feby/March [[/overwrite]] ^[[March]] 11th 1843
17

Made a number of experiments with the object
[[overwrite]] to [[overwritten by]] of [[/overwrite]] polar[[overwrite]] ize [[overwritten by]] izing [[/overwrite]] the phosphoregence emination, but was not successful. I however established the fact that the emination does not produce the phosphorescence when it is passed through a Nichols eye piece, combined of two pieces of calk spar, so arranged as to reflect under the extra ray - The light is much more vivid under two pieces of spar, making a thickness of 4 inches, than under an eye piece of one inch in thickness.
  The substance which is most impervious to the phosphorogence emination which I 
have as yet tried, is tourmaline. I can determine with some approximation to accuracy the comparative transfo[[blurred ink]] by making two holes in the same card and covering one with one substance and the other with another, the same powder being placed under each, the comparitive brightness gives the comparitive transmitting power.
  Part of the effect in reference to the now luminous result, when a Nichol's prism was used, may be ascribed to the fact that overly half of the incidental light passed through the crystal, the other half was reflected aside but result was so intense [[strikethrough]] when [[/strikethrough]] ^[[under]] the crystal and so feeble under the eye piece, that the difference cannot be attributed entirely to this cause.
  It appears to me that a simple polarized beam does not produce as much effect as a [[strikethrough]] a [[/strikethrough]] beam of ordinary light of the same quantity and intensity.
  I next placed a crystal of carbonate of lime above, and again below the eye piece, with the idea that the depolarization of the light

Transcription Notes:
09-28-14-BW JH seems to be using multiple misspellings of phosphorescence, or his own made up term for the phenonmenon: "phosphorogence" "phosphorigence" "phosporegence".