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[[start page]] 34 May 3rd 1843
 Next prepared some of the sulphuret of calcium, by mixing pounded calcined oyster shells with 1/3 of their weight of sulphur.
 First tried if this would become luminous by the galvanic spark, or rather from the coil with a rod of iron in its axis. The effect was apparently as great in proportion to the size of the spark, as in the case of the discharge from the Leyden Jar. The powder was supported on a plate of rock crystal, in order to hold it immediately over the mercury from which the spark was taken.
 I next tried if the emination from galvanic spark would pass through glass. The powder was removed to a plate of glass of the same thickness as the plate of rock crystal, but although the same number of sparks were taken, the powder remained quite dark. It would appear from this that the spark from mercury gives the same emination as as that from the electrical discharge.

 Tried the comparative transmissive power of glass and allum, found that [[underlined]] alum [[underlined]] was nearly the same as rock crystal.
 Next tried the polarizable capacity of the phosphogenic emination, found that it was polarizable, by placing one of the small trays which I made of sheet lead, under the mica pile of Mellom's apparatus [[image]] first with the mica horizontal, and again with the same inclined to the polarizing angle. A greater effect was produced with the latter position of the mica than with the former. The effect was not however as great as in the case of light.
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[[start page]]May 4th 1843  35
 Next arranged the apparatus for ascertaining the reflectability of the phosgenic emenations. [[image]] A [[underlined]] metallic [[/underlined]] mirror was arranged so as to throw the reflection of the spark down through a hole in a plate, underneath which the lime was placed, when the discharge was made the sulphuret of lime glowed very brightly.
 Found a source of error in the last experiment, the light direct from the spark was not sufficently screaned. Remedied, tried the experiment again, but the same result was produced. The lime was luminous and not much less so than by the direct discharge.
  Tried the same experiment with a peace of black glass. The result was the same, but the amount of reflected light much less than from the mirror of speculum metal.
  Repeated the experment of the polarization of the phos. emination, and from the result there can be no doubt of the fact of the polar capability of the emination. The mica pile was placed horizontally then the discharge made. The lime was dark, the pile was next inclined in an angle of about 33[[degree symbol]] with the ___ The spark, again pass. the lime now was luminous. The light was then suffered to disappear, the pile was returned to its horizontal position, no effect. The pile again inclined at the polarizing angle, now the lime exhibited a [[strikeout]] shining [[/strikeout]] shining surface.
[[image]]
This establishes the fact.
In the forgoing experiments, I used the apparatus for supporting the little pans which is represented in the margin.
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Transcription Notes:
source for "Sulphuret of lime" --> https://www.google.lu/search?q=phosgenic&ie=utf-8&oe=utf-8&rls=org.mozilla:en-US:official&client=firefox-a&channel=sb&gws_rd=cr&ei=ww7zU_bjBsO7ygOE44LgAw#channel=sb&q=sulphuret+of+lime&rls=org.mozilla:en-US:official 2014-10-10-BW JH uses phosphorogence and phosphogenic and other made-up forms related to phosphorescence, etc.