Swedish letter that I do not recognize

[Karen Kelsey]

I have had my ancestors letters from Sweden translated, which is helping me to write a family history.  I have inherited many photos and Bibles, and the owner's name is written in front of each Bible - in elegant script.  My farmor's mor received her Bible in 1876, and she signed her name as Mari Ahlgren,  Näsbyholm 1876.  However, there are two dots over the Y - which I cannot reproduce in this message.  I have seen the letters ä and ö, but I have never seen a Y that had two dots over it.  Was this a different letter in the 1870s, or did it indicate a different pronunciation?

[Jan Jutefors]

Karen,
 
You can read that Y as on ordinary Y, there is no different.

[Bo Skoglund]

The signs ? or ~ above some letters indicate that they are vowels as a help to distinguish similar letters. A dash above a consonant means that this letter should be double. Often used in older church records with so called German handwriting.