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50 Tuesday May 16th 1843

Repeated the experiment of rendering the sulphur[[retic?]] luminous under water after the substance had stood thus immersed 30 hours and more, it appeared as brilliant as that which had not been thus placed.

Submitted the sul of lime to the light of a candle and then examined it in the dark; found it phosphorescent. The phosphorogenic emination therefore exists in the light of a candle.

I have before found that alcohol is a bad transmitter of the phosgenic emination to test this again. I placed in a shallow glass vessel a few crystals of sulphate of potassa and over them about 3/4 of an inch of alcohol. The crystals [[strikethrough]] however [[/strikethrough]] remained dark when the discharge of electricity passed over them, although when they were shaped in water in the same way they glowed with great brilliancy.

Tried the transmissibility of white wax, found that the lime became luminous faintly below a plate of white wax 1/4 of an inch thick. 

Found that common chalk became quite brilliant by a discharge of the jar at the distance of 4 or 5 inches, also that the same screening influence was exerted by glass and other substances, - also the screening took place in the case of the light from the candle; this was not however as fully proved as it might be.
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Wednesday May 17th     51

  According to [[circled]] Becquerel [[/circled]], there are three substances which give light during a change of form from the [[insertion]] liquid to the [[/insertion]] solid [[strikethrough]] to the liqui [[/strikethrough]] state. Sulphate of potassa, [[circled]] arcenious [[/circled] acid, & muriate of ammonia. -- Since the sulphate of potassa is phosphoresent I thought that perhaps the other substances might be so also, tried the [[circled]] arcens [[/circled]], but got no result. It should have been however the crystallized transparent [[circled]] arcenic [[/circled]] and not the ordinary kind (Kane). 

Friday June 9th.
  Since the last date, I have been engaged in lecturing to the senior class, and have also attended the centenary anniversary of the american Phil society. At this meeting, I made a communication of the results of my investigation of the phosphorogenic emination. also gave an account of the method I have proposed for determining the velocity of a cannon ball. The meeting was well attended, 45 communications were made but I was not much impressed with the importance of this method of advancing science. The temptation to make a display and to bring forward communications merely to produce an effect for the moment is very strong, and while the mere declarations on the foundation of other men's labours produces quite an effect, the man of true science who modestly brings forth the result of his labours is scarcely noticed, provided he has arranged nothing for effect. These reflections are not made inreference to my own case, since I was more complimented than I deserved, but they are the sober inference from an attentive watching of the result of the meeting. I am not sure that the British association has much advanced the cause of science, except in the case of meteorology and magnetism.