422 MODELS FROM SERIAL SECTIONS [Ch. XI 



"The preliminary shaping having been accomplished, more exact 

 modeling is undertaken. The paper sections slide very easily upon 

 one another. The most satisfactory means of fastening them to- 

 gether is by the use of ribbon pins, ordinary pins, or wire nails of 

 various sizes, depending on the size of the model. No kind of paste 

 or glue was found suitable for this purpose." 



§686. Finishing the model. — " When the model is well formed, 

 inequalities are best removed by rubbing with the edge of a dull 

 knife and smoothing with sandpaper. Any dissections of the model 

 for showing internal structures should be planned for at this stage, 

 for it is now more easily separated than later. It is also at this time 

 that superfluous 'bridges,' which have been left in place to support 

 detached parts, would better be removed." 



"To finish the model it is held together firmly and coated with 

 hot paraffin either by a camel's hair brush or by dipping in paraffin 

 and removing the superfluous coating by a hot instrument. One 

 might use a thermo-cautery for this purpose." 



'The paraffin renders the model almost of the toughness of wood 

 without destroying the lightness of the paper." 



§687. Coloring the surface; dissecting the model. — "For color- 

 ing the surface of the model, it was found most desirable to use 

 Japanese bibulous paper, lens paper (§ 158) which had been dipped 

 in water color and dried. Any of the laboratory dyes or inks can 

 be used, such as eosin, picric acid, methylene green, black ink, 

 etc. The colored lens paper molds over the surface with ease and 

 is held in place by painting with hot paraffin. All color and 

 enumeration lines and fine modeling show through the transparent 

 paper." 



"When the model ceases to be a working model it can be covered 

 with oil paints mixed with hot paraffin and rubbed to any degree of 

 finish desired." 



"One can dissect a model by a hot knife run along the planes 

 of cleavage or cut across them by a saw." 



For the literature of blotting models see: Susanna Phelps Gage, 

 Amer. Jour. Anat., vol. v, 1906, p. xxiii; Proceedings of the Inter- 

 national Zoological Congress for 1907; Anatomical Record, Nov. 



