Morey on the Patent Water-Burner* 141 



place; water condensed in the empty ball, and soon froze 

 into a film, lining its interior. A few minutes after, a film 

 of ice began to form on the upper surface only, of the wa- 

 ter in the other ball, and gradually increased, till it was a 

 quarter of an inch thick. All this is what might be expect- 

 ed. But on gently moving the instrument, (it was merely 

 lifted, and not shaken,) the ball in which the water was 

 freezing suddenly burst with a considerable explosion, and a 

 pretty loud report. 



The apparent cause of this event, (which we have not 

 heard of before, as occurring with this instrument,) appears 

 to be, that as the water filled a full hemisphere, (and we be- 

 lieve a little more,) the film of ice first formed, and occu- 

 pying an equatorial plane, and therefore the largest diame- 

 ter in the sphere, could not recede in order to give room for 

 the expansion of the water, as it froze beneath. It would 

 therefore, in all probability, have burst, had it not been mov- 

 ed ; but, it is also probable, that the water beneath the ice 

 had been cooled to a point below 32°, and perhaps several 

 degrees below; when moved therefore, (agreeably to what 

 happens commonly in such cases,) the water below the film 

 of ice probably shot very suddenly into crystals, and thus, 

 not having room to admit of the requisite expansion, the 

 ball of course exploded.* This little occurrence was thought 

 worthy of being mentioned, both as affording illustrations of 

 laws and facts before known, and as suggesting an obvious 

 caution in forming the cryophorus — to introduce less water 

 than what will fill half the ball. 



Art. XVIII. — Remarks on the Patent Water-Burner ; By 

 Samuel Moret, {in a letter to the Editor.) 



Orford, July 30tb, 1823. 

 Sir, 



Trusting that I have in some measure reduced the Pa- 

 lent Water Burner, or Vapour Lamp, to a form that unites 

 utility with convenience, for general and domestic purposes, 

 I again wish to submit to your perusal, for a place in your 



* It is possible that adhesion between the glass and the ice might have 

 ^contributed to the effect. 



