PREPARATION OF TISSUES 9 



SKETCHING FROM THE MICROSCOPE 



Let us most emphatically urge the practice of sketching in 

 connection with microscopy. "I am no artist," or "I have no skill 

 in drawing," is often the reply to our advice in this matter. We- 

 then suggest that no special skill is needed to begin with, only 

 patience and a dogged determination to succeed. The pictures in 

 the microscopic field have no perspective, and may be reproduced 

 in outline merely. Begin with simple tissues, reserving intricate 

 detail until a short period of practice gives the technique needed. 

 We do not recommend the camera lucida, as our experience strongly 

 impresses us with this as a fact, that he who cannot sketch 

 without a camera will never sketch with one. Pencil drawings 

 may be very effectively colored with our staining fluids, diluted 

 if necessary. 



PREPARATION OF TISSUES FOR MICROSCOPICAL PURPOSES 

 TISSUES ARE STUDIED BY TRANSMITTED LIGHT 



The microscopical study of both normal and pathological tis- 

 sues is invariably conducted by the aid of transmitted light. 



Tissues, if not naturally of sufficient delicacy to transmit light, 

 must in some way be made translucent. 



Delicate tissues like omenta, desquamating epithelia, fluids 

 containing morphological elements, certain fibers, etc., are suffi- 

 ciently diaphanous, and require no preparation. Such objects are 

 simply placed upon the glass slip, a drop of some liquid added, 

 and, when protected by a thin covering glass, are ready for the 

 stage of the microscope. 



PREPARATION BY TEASING 



The elements of structures mainly fibrous e.g., muscle, nerve, 

 ligament, etc. are well studied after a process of separation, by 

 means of needles, known as teasing. A minute fragment of the 

 organ or part, having been isolated by the knife or scissors, is 

 placed upon a glass slip, and a drop of some fluid which will not 

 alter the tissue added. Stout sewing -needles, stuck in slender 

 wood handles, are commonly employed in the teasing process. 



