NO. 1863 BIBLIOGRAPHY OF CANAL RAYS — rULCHER 3OI 



II. GENERAL DESCRIPTION. 



When a discharge is passed through an exhausted tube divided 

 into two compartments by a perforated metal cathode, himinous bun- 

 dles of rays appear, extending from the holes in the cathode back 

 away from the anode. These are the canal rays, discovered and 

 named by Goldstein — 01(692,39). Similar rays may be obtained 

 with other arrangements of the cathode, but the rays obtained under 

 the simplest conditions, i. e., when the two compartments communi- 

 cate only through the perforations in the cathode, alone will be 

 considered in what follows. 



The rays move in straight lines except in a magnetic or in an 

 electric field. They excite glass and some other substances placed 

 in their path to fluoresce temporarily, thus rendering the place where 

 they strike them visible. They consist for the most part of positively 

 charged particles of matter,, with a mass not less than the hydrogen 

 atom. With these preliminary remarks, we proceed to give a sum- 

 mary of their properties as determined so far by experimental 

 research. 



Several authors have suggested changing the name from canal 

 rays (Kanalstrahlen) to anode or positive rays— W8(66o), 

 Ew3(300), Tm3(56i). By "canal rays" as used here is meant a 

 specific form of positive rays. 



For brief general discussion of canal rays, see the following: 

 Si; Tmi; Sm4; S4; Wlyi ; Ew3 ; Andi ; S17; Tm4; Tms ; Mm; 

 GR( 726-9) ; of which the most complete is Ew3. For photo of 

 rays see Prti Taf. VII, fi4. 



III. EXPERIMENTAL RESULTS. 



i. apparatus. 



Illustrations of Discharge Tubes. 

 Original tube: Gifi ; Sm4f49. 

 Simple tubes: Giff2 and 3; Bgifi; WSffi and 2; Wif2,- W3f3; Ewififi and 2; 



Boifi ; G3fi ; Si3f I ; Hbffs, 6 ; SHf i ; Tm7fi2 ; Mnifi;. 

 To show charge: Prniffi and 2; Vif6; WSffi, 2, 3 and 4; Ln2ffi 2- Auifi • 



Au2fi; Tm8f5. 

 To show magnetic deflection: W2fi ; W3f4; Wsfj; Sifiig; Wgffi and 2; 



S4ff224 and 225 ; Tm3f2 ; TmSffi, 2 and 6. 

 To show electrostatic effects: V3f2; W5ff2, 5, 6 and 7; W6f i ; Wpffi and 2- 



Si3f8; Tm3f2; Tm7f2. 

 To show fluorescence: Arif3; W7f i ; Sm2ffi and 2. 

 To show secondary emission: Tm2fi ; Fiffi and 2; Au2ffi, 2, 3 and 4; F2fi. 



