Mason Jones (1919 - 2009), the legendary long-time principal horn player of the Philadelphia Orchestra, accumulated the 53 mouthpieces shown below. As found they fall into four categories: mouthpieces in pouches, wooden mouthpieces, those boxed labeled "to be plated" and those he designated as "odd shapes, impractical." Aside from those in leather pouches, they were simply mixed in several cardboard boxes, hence the term "accumulation" is used rather than "collection." Most of them were probably sent to him unsolicited for his evaluation, although a couple were attempts to duplicate his own favorite.  

Mr. Jones carried his regular playing mouthpiece in a pouch in his pocket rather than in his horn case. Five mouthpieces are in pouches as shown below. According to the liner notes of his Music Minus One recording (MMO  8047, 1973) "For this Laureate Series Recording, Mason Jones used a German silver Horner Model Kruspe double horn made in 1936. He used a Kruspe mouthpiece with a narrow flat rim and funnel interior." In a 1978 video recording he can be seen playing on a gold-plated mouthpiece like the one identified as "MJ Kruspe 1" in the table below. It is assumed that this or the silver-plated one labeled "MJ Kruspe 2" were his daily drivers. (Note: in the tables below designations enclosed in brackets, [ ], are only for reference in this article and were not indicated by Mr. Jones.)

Also pictured below is a Bach number 18 mouthpiece labeled with adhesive tape "my first" with its original velvet-lined wooden case. It is probably the one Mr. Jones used while he was a high school student in Hamilton, New York, before beginning his studies with Anton Horner at the Curtis Institute, Philadelphia in 1936.

Two other apparently Kruspe mouthpieces are shown with essentially the same dimensions¹ but approximately 1 cm. shallower interiors. They are very similar to the mouthpiece seen at left in a photo of Anton Horner. In notes accompanying the mouthpiece collection, Mr. Jones mentions loaning out a "Berv Kruspe mouthpiece." Arthur Berv had also been a student of Anton Horner and was Mr. Jones' predecessor as principal horn in the Philadelphia Orchestra. He also played a Horner model Kruspe horn, so it is assumed that these had been either Mr. Berv's or possibly Mr. Horner's mouthpieces. They are labeled "Berv Kruspe 1" and "Berv Kruspe 2."

Finally, there is a a custom fllugelhorn mouthpiece by Philadelphia maker Vincent Dell'osa, having the same inside diameter as the Kruspe horn mouthpieces but with a slightly wider rim. Mr. Jones owned a flugelhorn which he was known to play on occasion for particularly high baroque pieces such as the cantata's of J.S. Bach.² There are several other flugelhorn mouthpieces in collection but they have somewhat wider rims