TY - JOUR AU1 - Sharpe, J W AB - Ioosr are attachctl to the tops of the sidc-plates on the wedge- process takes about two minutes. 'I'hc dimensions of the \vcdg~~-pIilt<' arc 5 x .+ x : in. Above ancl on each side (if the plate. plate is a brass strip with a groove to forrn guir1c.s for the In conclusion the author wishes to thank blr I). A, riiow"nt of the plate-carrier. A channc.1 is cut along thc Richards for advice and fruitful suggestions in tlic design length of the wetlg:r-plate to allow for the movement of the of the instrument and Profcssor 11. RI. Davies for constructive Irad-screw. 'I'hc ball-catch consists of a steel ball-bearinji of :I ' criticism and for the facilities phccd at his idisposal. I I~ in. diameter loaded by a spring resting in a hole drilled in the wedg:c. 'he chains which arc shown in Fig. 3 hanging Laboratory and Workshop Notes The Editor invites tlre srrhirrissioir of contrihritioirs to this sectiotl. The devices tlrsrvihed nred riot izecessttri1.v hr origiml; 10s. is poid for r(ic/r mtc pirhlislied, or trlt~rnntively n limited r~roirhev o,f reprirzts cniz he srrpplierl. A Graticule for Particle Size Analysis with the Electron Microscope. Ijy J. W. sfIAI