^ MICROSCOPE IN MANUFACTURES 



There are an extraordinary number of vegetable 

 fibres which are woven into articles of commerce, 

 of one kind and another. Then again, many fibres 

 are so short or so brittle that they cannot be woven 

 but are used for other purposes such as filling 

 cushions, cheap bedding, etc. There are also a 

 certain number of vegetable fibres which are valu- 

 able because they are stiff and bristle-like as well 

 as durable, and they are used for brushes, door 

 mats and for similar purposes. To the microscopist 

 who is interested in this work there is a wide field 

 open. 



For the examination of paper, which may be 

 described as a ''felt of finely divided fibres," the 

 microscope is invaluable. The essentials of a good 



i paper are that it be durable, that it retain its colour 

 and not become brittle. The least observant of us 

 cannot fail to have noticed that there are an ex- 

 traordinary number of different kinds of paper, not 



' only the many kinds which the paper manufac- 

 turers could show us, but the obviously varied 



; papers which we meet with every day. Added to 

 the papers, there are cardboards which are really 

 a kind of paper. It is clear, therefore, that 

 the man who can tell us exactly how any and every 

 paper is made and what it is made of has laid up 

 a goodly store of knowledge. In carrying out tests 

 of paper we rely partly on chemical and partly on 

 microscopic tests. 



A number of substances contribute to the manu- 

 facture of paper; linen and cotton rags, hemp and 



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