428 Isleieorohgy . 



fame dilatation in congealing. To find then the greateft 

 fpecific gravity of water, wc ought not to take ice, for we 

 know that it fwims on water. We muft make choice of a 

 certain degree of heat between that of congelation and that 

 of expanfion. Experience has determined this point to be 

 about 41- of Fahrenheit. Confequeniiy, to find the greateft 

 quantity of water which can be contained in a veflel of a 

 given capacity, we muft take water at that temperature. 



This circumftance ihould be attended to in determining 

 meafures of capacity. Some people are fo well aware of it 

 that they buy liquids in cold, and endeavour to fell them in 

 hot weather. 



METEOROLOGY. 



On the 10th inft. about twelve o'clock at night, a re- 

 markable meteor was obferved by one of the matters of the 

 Free-fchool at Alnwick, and another perfon; it appeared 

 in the fouth-weft, at a confiderable altitude. At firfl it was 

 no bigger but far brighter than a common ftar, but prefently 

 expanded 1 into the form and fize of an apothecary's peftle. 

 It was then obfcvired by a cloud, which was ftill illuminated 

 behind ; when the cloud was dispelled, it re-appeared with 

 a direction fouth and north, ^yth a fmall long ftreamer, 

 cutting the peftle a little below the centre, and ifliimg awav 

 to the eaflward. It was again oifcured, and on its re-ap- 

 pearance, the ftreamer and peftle had formed the figure of a 

 hammer, or a crofs; prefently after the ftreamer, which 

 made the fhaft to the hammer, or ftalk to the crofs, affumed 

 two horns, at the extreme point towards the eaft, refcmbling 

 a fork. It was then obfeured a third time, but when the 

 cloud paffed over, it was changed into the fh&pe of two half-- 

 moons > back to back, having a fhort thick luminous ftveam ' 

 between the two backs ; it then vanifhed totally from their 

 fights It is ohicrvable, . new appearance became 



brighter and brighter, till it became an exceedingly bril- 

 liant object, all the other ftars in comparifon appearing to 



