206 Me. James Napieu's Analysis of Stone fused hy Lightning. 



proportioned as, cceteris parihus, to increase that resistance, and to make 

 the rotatory velocity decrease more rapidly (namely, by, amongst other 

 alterations, placing the rotating mass at a greater distance from the 

 point), but the curves will be larger and continue longer — instead of the 

 reverse, as Major Barnard would lead one to expect. 



Specimens of Silicon, Boron, and some other rare elements, were 

 exhibited by Dr. Anderson. 



Mr. Keddie read the following analysis by Mr. James Napier, chemist, 

 of a small portion of the stone fused by lightning, in May, 1854, exhi- 

 bited at the meeting of the 27th January. The stone, which was a 

 frao-ment of one of the turrets of the tower of Glencairn Parish Church, 

 was given to Mr. Keddie by Robert M'Turk, Esq. of Hastings Hall, 

 Glencairn, and is now deposited in the Museum of the Andersonian 

 University : — 



" I took a small sample of the fused stone, and also a piece of the 

 stone not fused, apd submitting them to analysi,s obtained the following 



results : — 



Original Stone. 



"Silica, 88-5 



Peroxide of iron, 

 Alumina, 



Carbonate of lime, 

 Magnesia, 

 Moisture, 



2-5 

 4-5 

 2-5 

 1-0 



1-0 



100-0 



" The fused stone was a fair glass, opaque and brittle, indicative of 

 rapid cooling. 



" The analysis gave — 



"SiUca, 84-3 



Protoxide of iron, 

 Alumina, 

 Lime, 

 Magnesia, 



2-9 

 4-8 

 3-2 



1:6 



100-0 



" The only change is the reduction of the peroxide of iron to the 

 state of protoxide. There is also more lime, iron, and magnesia ; but 

 this may be accounted for by the sample of the stone that I took, being 

 from the outside, having lost these ingredients from being exposed to 

 moisture or rain, — these being the matters that would be dissolved out 

 of stone by the access of water. The analysis is interesting as showing 

 how rapidly chemical action must have taken place." 



