REPORTS OF SOCIETIES, 



95 



mile from Perth, on the Old Scone road, but in small quantity. It may have 

 escaped from a garden for ought I know. He only collected one plant as he 

 said it was all he saw. 



Sanguisorha canadensis. I observed this plant about a mile east of 

 Perth, growing in a dry ditch several years ago, but passed it over unre- 

 corded until a specimen or two of it Avas collected by Dr. White, Jun. Its 

 situation is on the north side of the Tay, about fifty or sixty yards from its 

 margin and beyond floodmark even at the river's greatest height. This plant 

 has even more the appearance of being indigenous than either Silene armeria 

 or Petasites fragrans, as it is much further distant from human habitations. 

 Has it ever been observed under "similar circumstances by any other British 

 botanist ? I am sorry that owing to personal ill health and severe domestic 

 affliction I have been unable to procure specimens of these rarities for distri- 

 bution among my botanical friends. 



Bridge End, Perth, 2ith August, 1866. 



QUECKETT MICROSCOPICAL CLUB. 



The usual monthly meeting was held in 

 the Library of University College, on the 

 28th ult. (September), W. Hislop, Esq., 

 vice-president, in the chair. 



A paper was read by Mr. R. T. Lewis, 

 * ' On some of the microscopic effects of the 

 Electric Spark," detailing a number of 

 experiments made by him, between Dec. 

 1865 and the present time. They were 

 suggested, in the first instance, by the cir- 

 cumstance of having placed a card, which 

 had been perforated by powerful Induction 

 sparks, upon the stage of the microscope, 

 to examine the raised burrs produced, when 

 he was surprised to observe that all such 

 holes as were clear were of pentagonal shape. 

 In consequence of this observation pieces 

 of paper and card of various kinds were 

 produced, and perforated by sparks, of 

 various lengths, from difi'erent Induction 

 Coils, in all of which cases the pentagonal 

 form of hole prevailed : and the same result 



was also found when discharge sparks from 

 aLeyden jar charged withfrictional electri- 

 city were employed. Subsequently a con- 

 trivance (which was described) enabled 

 these experiments to be repeated upon the 

 stage of the microscope. The effect of 

 sparks upon paper chemically treated, the 

 leaves of plants, mica, thin glass, film of 

 egg, &c., was described ; from which it 

 appears that the perforations were generally 

 five-sided, without regard either to the 

 shape of the points between which the 

 sparks were discharged, or to the texture 

 of the material perforated. The paper was 

 concluded by a few remarks to the eff'ect 

 that electricity, thus brought under the 

 microscope, would be found to afford both 

 amusement and instruction, whether in 

 connection with the use of the micro -spec- 

 troscope, or in observing the effects of 

 electrolytic action. 



Eight members were elected, and twenty- 

 eight gentlemen proposed for membership. 



The meeting terminated with a conver- 

 sazione ; and amongst other objects exhi- 



