Xll LIST OF ILLUSTRATIONS. 



PAGE 



25. Special Polishing Machine .. .. .. .. .. 137 



26. Oven for Drying the Nickeled Pieces .. .. .. .. 139 



27. Simple Bath .. .. ' 169 



28. Hydraulic Press for Moulding Woodcuts .. .. .. 173 



29. Plumbago Coating Machine 174 



30. Plate-drawing Machine .. .. .. .. .. .. 179 



31. Finishing Machine .. .. .. .. .. .. 180 



32. Gramme Machine for the Refining of Copper .. .. .. 200 



33. Wilde Machine 208 



34. Siemens Machine 210 



