REFERENCES 



Transverse spacing of electrodes — Lateral spacing of electrodes is some- 

 what more difficult to achieve than longitudinal. The microcapillaries 

 have to be fixed relative to each other with 'spacers' between or with wax. 

 The electrodes are brought into place with the aid of a simple manipulator 

 under a microscope. A manipulator which has been used is simply made 

 of two L shaped pieces of Perspex, each provided with a vertical slide in 

 addition, and grease between the sliding parts (Figure 35.19). Minute 



.^ 



- '/////yy/////A .. . 



— |Hypodermic 

 needle 

 — CD 



^ 



-Sliding surface 



Sliding surface 



Figure 35.19 Section through a simple manipulator used for constructing 



a group of electrodes 



quantities of Picene or other wax can be applied with the aid of a simple 

 tool resembling a soldering iron. This consists of a thin wire soldered to a 

 piece of thick wire which is surrounded by a small low voltage heating coil. 

 The wax is applied while the tips are supported in place, as otherwise they 

 are drawn together by the surface tension of the wax when fluid. 



A combination of longitudinal and lateral spacing has been used to form 

 different patterns of recording electrodes. 



REFERENCES 



^ HoDGKiN, A. L. and Huxley A. F. Resting and action potentials in single 



nerve fibres /. Physiol. 104 (1945) 176 

 ^ Curtis, H. J. and Cole, K. S. Membrane resting and action potentials from 



the squid giant axons J. Cell. Camp. Physiol. 19 (1942) 135 

 ^ Ling, G. and Gerard, R. W. The normal membrane potential of frog sartorius 



fibres J. Cell. Camp. Physiol. 34 (1949) 382 

 * Brixton, H. T, S. Hydrogen Ions London; Chapman & Hall. 1955 

 ^ Caldwell, P. C. Measurement of intracellular pH by means of a tungsten 



microelectrode /. Physiol. 124 (1954) p IP 

 ® Eccles, J. C. The Physiology of Nerve Cells Oxford University Press. 1957 

 ■^ Nastuk, W. L. and Hodgkin, A. L. The electrical activity of single muscle 



fibres J. Cell. Comp. Physiol. 35 (1950) 39 

 8 MoREY, G. W. The Properties of Glass New York; Reinhold. 1938 

 ^ Hodgkin, A. L. Personal communication (1957) 

 ^" Temtleton, C. C. Drawing of small uniform glass capillaries by electrical 



beating Rev. sci. Instriim. lA (1955) 880 

 ^^ Weale, R. a. a method for drawing microcapillary tubes /. Physiol. 112 (1950) 



4P 

 ^^ Brock L. G., Coombs, J. S. and Eccles, J. C. The recording of potentials from 



motor neurones with an intracellular electrode /. Physiol. 117 (1952) 431 

 ^^ Kao, C.-Y, a method of making prefilled microelectrodes Science 119 (1954) 



846 

 " Grain, S. M. Resting and action potentials of cultured chick embryo spinal 



ganglion cells J. Comp. Neurol. 104 (1956) 285 



38 565 



