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paper by which two copies of a bill are made at one writing is a 

 yet further example of the use of lamp-black. For taking rubbings 

 of monumental brasses a composition known as heel-ball is em- 

 ployed. The primary use of heel-ball is for blackening the heels 

 of boots and shoes. This suggests the various blackings, pastes, 

 polishes and varnishes having a carbon basis and serving to pro- 

 tect and beautify the leather of our boots and shoes. 



For the "Carbon process" used in photography a film of 

 gelatine is intimately mixed with very finely divided carbon and 

 sensitized by ammonium bichromate. This process has, I believe, 

 been used in making the extensive "Autotype" series of repro- 

 ductions of celebrated paintings, but it is, perhaps, only fair to 

 say that other pigments sometimes replace the carbon. When 

 a piece of glass is passed through a candle flame it becomes coated 

 with a layer of lamp-black. Such smoked glass is useful for 

 observing the sun during the progress of an eclipse or for ex- 

 amining its disc when affected by sun-spots large enough to be 

 visible without telescopic aid. Another use of smoked glass is in 

 the preparation of lantern slides. Slides of this kind can be very 

 rapidly made and many of us have learned the results of Parlia- 

 mentary elections by this means. 



I began with the diamond as a means of personal adornment. 

 The form of carbon easily obtained by scorching a cork is used, if 

 not as an adornment, as a part of the professional get-up of the 

 street minstrel. Indian ink, or some similar preparation, is used 

 in tattooing, a form of decorating the person very widely diffused. 

 By way of conclusion to my remarks on the artistic uses of carbon 

 I may remind you of three important media used in drawing : 

 charcoal, Indian ink, and the pencil. Each of the three has its 

 own advantages and limitations, but of these I am not competent 

 to speak. 



The electrical applications of carbon are very numerous. 

 One or another form of it is used in the arc lamp, in the construc- 

 tion of Leclanche" and other cells, in a great many electrolytic 

 operations both on the manufacturing and the exper mental scale, 

 in the making of collecting brushes for dynamos, in some forms 

 of telephone and microphone receivers and for many other pur- 

 poses. 



Here I bring to an end my catalogue of uses of the element 

 carbon in a free or uncombined state. To attempt to recount the 

 uses of the compounds of carbon would be a hopeless task. Every 

 substnce of animal or vegetable origin might be cited, every 

 article of food and of clothing besides the huge number of com- 

 pounds which the art of the chemist has prepared from coal, wood 

 and petroleum. Again, we are at present almost entirely de- 

 pendent for artificial heat upon the combustion of carbon or 

 carbon-containing substances, so that, indirectly, carbon is re- 

 quired to enable us to make use of the mineral wealth of the 

 world. A complete account of the uses of carbon and its com- 

 pounds would be but little short of an account of human life in 

 its material aspect and of all the arts of war and peace. 



