Caribbean. He made drawings, color notes, and preserved some 

 specimens to be taken back to the studio in Germany for use in 

 preparing models. While he was in the United States on a similar 

 mission in 1895, his father died, and he returned to his home 

 immediately, never to return to Cambridge. Following his 

 father's death, Rudolph continued making the plant models but 

 in reduced numbers each year. 



The question as to how the models were made by the Blasch- 

 kas and the existence or non-existence of "secrets" connected 

 with their manufacture has been rather controversial. It can be 

 said that, for all intents and purposes, there were no "secrets. 1 ' 

 Their methods for working with glass were known to other 

 glass-workers at the time. No doubt certain techniques were 

 handed down to them in the family which had for generations 

 worked with glass. Furthermore, they had themselves probably 

 developed approaches to their work that may have been unique. 

 The singularity of their work was due to the combination of 

 their various talents. They were both well grounded in the natu- 

 ral sciences. This familiarity was founded, not only on formal 

 instruction in the classroom, but to a great extent on observa- 

 tion and study of the flora and fauna of their surroundings. 

 Coupled with this was their possession of a highly developed 

 artistic sense. 



As to the actual creation of the models, we know that the 

 heated glass was manipulated and shaped in various ways 

 through the use of simple implements: pincers, tweezers and 

 other small tools of their own devising. The various parts of a 

 model were assembled with the use of the blow-flame and, in 

 some cases, various parts, such as long slender stems, were 

 strengthened by the inclusion of wire. Occasionally, some of the 

 parts were formed of colored glass in which case the part was 

 considered finished. In other instances, when the parts were 

 formed of clear glass, they were assembled, and the surface was 

 coated with a material incorporating mineral pigments. This 

 technique was used for many of the plant models as well as for 

 all of the invertebrates. 



Preliminary analysis of the material that they used indicates 

 that it was either a gum or glue or a combination of both. 



44 



