May 7, 1915] 



SCIENCE 



683 



meclianically, in vacuo; the apparatus, more- 

 over, occupying but a small volume. The 

 writer ventures to suggest the apparatus de- 

 scribed below as being one which embodies the 

 above essentials; the electrodes being substan- 

 tially the same as those used by Winchester, 

 which were in the form of circular loops of 



2 mm., wire, 7 cm. in circumference, and 1 mm. 

 apart. 



Referring to Fig. 1, the electrodes are two 

 straight parallel aluminium rods B^, B2, 2 or 



3 mm. in diameter, and 8 cm. long. They are 

 fastened to the glass tube T^ by being bent 

 around the ends of this tube, shown clearly in 

 the horizontal section. Fig. 2. 



and iJj in turn by means of another strong 

 electromagnet, M^ — the cutting stroke being 

 in the direction of the arrow. This operation 

 scrapes but one side of each rod, B^, B,. To 

 scrape the other two sides, A must be turned 

 through 180°, which is accomplished by turn- 

 ing M^, M^ through this angle. After the rods 

 have been cleaned. A, L, is moved into the 

 tube T^, out of the way. It will be noticed 

 that the apparatus is, essentially, a " spoke 

 shave " in vacuo. 



By using the above tube after the electrodes 

 have been cleaned in pure (electrolytic) 

 oxygen, it should be possible to demonstrate 

 conclusively the transference of oxygen into 



This tube, T^, is held in a larger tube, T,, 

 by springs S^ and S„ (wires), the ends of 

 which fit into dents in the glass tubes Tj and 

 T„. Leading-in wires w^ and w„, attached to 

 the ends of B^ and B„, respectively, are sealed 

 into the two side tubes t^ and i,, Fig. 1; said 

 side tubes connecting with a pump and a 

 spectroscopic tube of the usual type. 



A cutter, C, of hardened steel is attached by 

 a flexible brass rod, L, to an armature, A. 

 The cutting edge, £", Fig. 3, is semi-circular, 

 to fit the rods B^ and B,. The armature A 

 has small brass rollers at the corners, to pre- 

 vent scratching the inside of T^, and can be 

 moved back and forth within this tube by 

 means of electromagnets, M^ and M^. 



While the armature. A, is being moved in 

 the tube, the cutter, (7, is pressed against B^ 



helium and neon, if such indeed exist. On the 

 other hand, if (as seems more likely) the 

 helium and neon which appear in vacuum 

 tubes have previously been occluded by the 

 metal from the atmosphere, it should be pos- 

 sible, by means of the apparatus, to study the 

 rates of, and the conditions governing, such 

 absorption. 



It is by no means certain, however, that the 

 action in question consists simply in the libera- 

 tion of absorbed gases, for Sir J. J. Thomson^ 

 has discovered evidence of a genuine produc- 

 tion of helium and X3 from elements (lead) 

 and chemical compounds (salts of sodium and 

 potassium) which suggests an actual atomic 

 change, if not a genuine disintegration. The 



Sir J. J. Thomson, Eoy. Soe., Proc, Ser. A, 

 89, pp. 1-20, August 1, 1913. 



