MICROSCOPE IN MANUFACTURES 



various fibres are the most commonly used, not 

 forgetting wood pulp which we shall mention in a 

 moment. The finest and whitest paper is made 

 from linen rags and that from unused linen and 

 hemp is the strongest. Without attempting to 

 describe in detail or even in outline the different 

 processes which the various vegetable fibres must 

 undergo before they appear in the guise of paper, 

 we may say the treatment is very drastic. Strong 

 chemicals and machinery designed to reduce the 

 fibre to the finest possible particles render the 

 examination of paper, for the purpose of discover- 

 ing its composition, far from easy. Such fibres as 

 survive the rough treatment are mere fragments yet 

 they are often large enough for the lynx eyed micro- 

 scope to read their story. Formerly the constituents 

 of most papers could be separated into three classes 

 according to their behaviour with iodine solution, 

 but this test has been superseded by more compli- 

 cated methods which do not concern us here. 



The examination of various papers may prove 

 interesting for example in linen rag paper, we ought 

 to find some flax fibres, they will be sadly bat- 

 tered and torn but are usually recognisable under 

 the microscope. Hemp paper is tough and is used 

 for bank notes, in it some of the short tow fibres 

 will probably occur and they will give a clue to its 

 composition. Cotton rag paper is easily recognised 

 for the fibres are very characteristic, a remark which 

 also applies to jute paper, the so-called manila used 

 for envelopes, wrappers, etc. 



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