IO8 THE A B C OF PHOTO - MICROGRAPHY 



are " bone dry," and it must always be done 

 by one steady pull ; a succession of them will 

 leave a series of disfiguring creases across the 

 print. The ferrotype plates should be care- 

 fully laid away from dust in a drawer or box 

 face to face, with a sheet of tissue paper 

 between. When taken out for use they 

 should always be carefully washed with a tuft 

 of cotton wool, as already described. It will 

 not do any harm to wipe them occasionally 

 with a soft cloth and a little coal-oil, followed 

 by a perfectly dry cloth, always quite soft, to 

 avoid danger of scratching the polished 

 surface. 



Blue prints, when carefully made on suit- 

 able paper, are very satisfactory for many 

 classes of objects, pleasing the artistic eye 

 and rendering delicate details with astonish- 

 ing fidelity. The ordinary commercial papers, 

 however, are totally unsuited to our work; 

 their surfaces are not smooth enough, nor are 

 the whites at all pure. Every photo-micro- 

 grapher who elects to use this method of 

 printing should prepare his own paper, hence 

 I am led to give a few simple directions for 

 so doing. The best paper for the purpose 

 with which I am acquainted is Rives'. It is 

 pure linen, of medium weight, heavily sized 



