This is only a suggestion but it is possible that your Boom ancestor is a descendant of the German Palatine BOHM family. The emigrant Hendrich Bohm came in 1710 to Dutchess Co NY ( addressed on p. 80 of "The Palatine Families of New York" by Henry Z. Jones Jr.. ) Members of this family are found in Ulster Co NY church records with varying spellings of this name (Boehm, Beem Beam etc.....and maybe in later generation Boom). Of course everyone spoke Dutch and actually thought of themselves as Dutch culturally. Many married into Dutch families and in later generations heard that their ancestors were Dutch. (some probably were!). My grandmother was an Ulster Co SMITH and I have now found that she descended from the German SCHMIDT family. (My uncle insists that there was never any mention of German ancestors....probably not..they melded into the Dutch culture very early on..the name for a while was seen as SMIT.) My SCRIBER grandfather's ancestors were orginally SCHREIBERS then SCHRYVERS. The early Dutch Colonies were made up of English, German, Dutch and French Huguenots....as well as those of a number of other ethnicities. The names sometimes took on Dutch spellings or odd phonetic ones as the ear heard them. Some patronymics became surnames as well as others based on places of origin and others came from some sort of "nickname" that described the individual. Susan