XI, 1. Patten: Orienting small objects for sectiouing, etc. 13 



Orienting' small objects for sectioDlng^, and fixiug" 

 them, when mounted in cells. 



By 

 William Patten, 



Dartmouth College, Hanover, N. H., U. S. A. 



In one of the recent "Contributions from the Zoological Laboratory 

 of the Museum of Comparative Zoology", Vol. XXV, no. 3., Dr. W. 

 McM. WooDWOETH* describes a method of orienting small objects for 

 the microtome. His method was developed, he states, from one first 

 used by myself. To avoid any misunderstanding, I will say that in 

 answer to a letter from my friend Dr. Woodworth asking permission 

 to Hse or describe my method, I replied that he was at liberty to 

 make what use of it he saw fit, or words to that effect. I refer to the 

 subject here, partly becanse Dr. Woodwoeth does not State what the 

 original method was or how he has modified or added to it, but mainly 

 because I believe the original method is much simpler and better adapted 

 to the purpose than his. 



My method, which is especially useful when one desires to orient 

 accurately large numbers of small and similar objects, is as follows : — 



Small Strips of writing paper with two sets of raised parallel lines 

 running at right angles to each other are cut, and at suitable intervals 

 a very small drop of coUodion and clove oil, about the consistency 

 of thick honey, is added. The drops are arranged close together 

 along one of the ribs that run lengthwise of the paper. The object to 

 be imbedded is cleared in clove oil, or oil of bergamot — not tur- 

 pentine; the latter dries too quickly, so that air brittles are likely to 

 form in the object; and besides it does not mix readily, as it should, 

 with the thick coUodion. It is then raised on the point of a knife and 

 after the excess of oil is drawn off, transferred to a drop of the thick 

 coUodion. It may be adjusted at leisure under the Compound, or the 

 dissecting microscope and will stay in any desired position. 



When half a dozen or more objects are oriented in reference to 

 the Gross lines (which are to be parallel to the section planes) the 



») See this Journ. vol. XI, 1894, p. 31. 



