393 



he noticed .the rude adaptation of the quern stones to the 

 purposes of a water-mill. 



From a curious book, entitled " the Montgomery Manu- 

 scripts," written about 1648, Mr. Smith quoted a description 

 of a similar attempt in the Barony of Ardes, County of Down, 

 in Ireland, to convert a hand-mill into one driven by water, 

 in which " the axle stood upright, and the small stones, or 

 querns, such as are turned with hands, on the top thereof. 

 The water-wheel was fixed at the lower end of the axletree, 

 and did run horizontally among the water, a small force 

 driving it." 



In conclusion, Mr. Smith pointed out the progressive im- 

 provement in the form of the quern, — from the pair of rude 

 oblong stones, which ground the corn by simple tritura- 

 tion, to the rotatory mortar-shaped quern ; thence to the 

 rounded or rather hemispherical form ; and concluding with 

 the two flattened stones, similar to those used in the water- 

 mills of the present day. 



The Rev. Mr. Todd exhibited to the Meeting a/ac si- 

 mile of a remarkable papyrus roll preserved in the British 

 Museum. 



The Secretary read the following communication, entitled 

 '* Justification of Mrs. Somerville's Experiments upon the 

 magnetizing Power of the more refrangible solar Rays."* By 

 George James Knox, Esq. and the Rev. Thomas Knox. 



Professor Morichini of Rome was the first to observe 

 that steel, when exposed to the violet rays of the solar spec- 

 trum, becomes magnetic. Similar experiments were tried by 

 Mr. Christie, in 1824 ; but the most accurate experiments 

 upon this subject have been performed by Mrs. Somerville, 

 in 1825, who determined that not only violet, but indigo, 

 blue and green, develop magnetism in the exposed end of 



* rhil. Trans, vol. cxvi. 1826. 



