BOTTLES AND VIALS. 59 



the details of structure. The following conventional colors 

 are generally adopted : 



Red, heart and arterial circulation. 



Blue, veinous circulation. 



Green, In ei. 



Purple, kidneys. 



Yellow, ovaries. 



Orange, testes. 



Brown, alimentary canal. 



Neutral tint, nerves. 



Large labels can be easily written with the "Audiographic 

 Pen," invented by Mr. D. S. Holman, of Philadelphia. This 

 has since been extensively sold under the name of "Automatic 

 shading Pen," and can be obtained at any stationery store. 



