Rabbi Jacob Bachrach's original autograph manuscript of his book Ishtadalut Im Shadal where he declares unequivocally that God's holy name is correctly pronounced Yehovah:
Ishtadalut Im Shadal, 1890, Jewish Theological Seminary, Manuscript 2883, Page 178, Section 134 [Page 127, Section 136 in the 1896 printed edition]"...the vowels Sheva Cholam Kamatz [=Yehovah] are not the vowels of the title Adonai, but they specifically belong to the Unique Name alone. There is not a single vowel here that comes from, or remains from, a reference to the title Adonai, [or even hints at it]. With these vowels, the priests in the Temple used to call on the Unique and Explicit Name the way it is written..."
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