35 2 [Proc. B.N.F.C, 



given out by long Giessler tubes, without contact with the 

 wires. The action of the current in the Crookes vacuum tube 

 was then shown, and afterwards a large number of objects were 

 exhibited, such as the hand, wrist, and elbow, a bag with 

 pincers inside, a book with scissors, and many more, including 

 a sheet of aluminium, which was quite transparent, and a sheet 

 of plate-glass, quite opaque to the rays. In addition to this, 

 W. J. Walker had on view what he humorously described as 

 " X rays by diffraction," which deceived many until they were 

 enlightened. This ingenious, yet simple, trick consists in 

 looking at the outstretched fingers against a bright surface 

 through an ordinary feather. The effect of the diffraction of 

 the light by the feather is to show what looks wonderfully like 

 the bones of the fingers. The side hall was devoted to the 

 lantern, skilfully worked by Lizars & Co., where crowded 

 audiences were delighted with the exhibition of a comprehen- 

 sive series of slides depicting botanical, geological, and 

 archaeological subjects, the photos shown being the work of F. 

 C. Bigger, Professor Cole, W. J. Fennell, W. Gray, A. R. 

 Hogg, Dr. MacWeeney, J. St. J. Phillips, and R. J. Welch. 

 In connection with the photographic section were likewise 

 shown the albums in connection with the club's archaeological 

 and geological survey of Ireland, containing about 400 platino- 

 type photographs of Irish subjects, in addition to a number of 

 other photographic albums and some views illustrating the last 

 season's excursions. A collection of photos of wild flowers in 

 their natural habitat by that capable artist, R. J. Welch, was 

 much admired. The exhibits of the botanical section were 

 highly attractive, comprising choice British and exotic ferns, 

 illustrated by fresh-cut fronds and growing plants, supplied by W. 

 H. Phillips (honorary treasurer) and Charles M'Kimm (curator 

 of Botanic Gardens Park) ; plants collected during the season 

 by R. Lloyd Praeger (honorary secretary of the Dublin Field 

 Club), Professor Edmund J. MacWeeney, of Dublin, exhibited 

 some bacterial cultures and slides, and a select series of Irish 

 fungi, including some that cause disease of the potato plant. 



