Blackford Condit, in his The History of the English Bible writes of the American Bible Union Version:
The American Bible Union was organized by seceders from the Baptist American and Foreign Bible Society. The object of this organization was "to procure and circulate the most faithful versions of the Sacred Scriptures in all languages throughout the world." Accordingly the Union provided for a revision of the New Testament by a number of scholars working independently of each other. The preliminary work was done between the years 1850 and 1860. This tentative work was printed on a large page, in three columns, with the Greek text in the center, the Common version on the left, and the New revision on the right, for the sake of convenient comparison, and sent forth inviting suggestions and criticisms. In 1866 the second revision of the New Testament was published in New York. The work of revision was extended to the Old Testament also. The revision of the book of Genesis was published in 1868, the Psalms in 1869, and Proverbs in 1871; Joshua, Judges and Ruth were issued in 1878, and the prophecy of Isaiah is in process of being stereotyped. In a statement of the Board made in May, 1878, they say that "on the whole Pentateuch exhaustive labor has been bestowed, as, indeed upon the whole Sacred Canon, the lack of funds alone holds them back."
In printing, the paragraph form is adopted, though for the sake of reference the numbering of chapters and verses of the Authorized version is retained, excepting in cases where such numbering breaks the connection. Another peculiarity in the printing is that poetical passages are put in the form of poetry. The following important rules were prescribed for the revisers as guides in their work:
I. The Greek text (Textus Receptus, Recieved Text), critically edited, with known errors corrected, must be followed.
II. The Common English version must be the basis of revision, and only such alterations must be made as the exact meaning of the text and the existing state of the language may require.
III. The exact meaning of the inspired text, as that text expressed it to those who understood the original Scriptures at the time they were first written, must be given in corresponding words and phrases, so far as they can be found in the English language, with the least possible obscurity or indefiniteness.
The names of such Biblical scholars as Doctors Conant, Hackett and Kendrick, connected with the revision, give assurance of great excellence in the work. And yet by the one peculiarity, in the use of immerse, the translation limits itself to the Baptist denomination.
In my experience though, the use of "immersion" in place of the transliterated form of "Baptize" was not that uncommon. I have here a transliterated Greek text of Mark 10:38 which has three forms of the word "Baptize." DUNASQE PIEIN TO POTHRION O EGW PINW H TO BAPTISMA O EGW BAPTIZOMAI BAPTISQHNAI, or if you will: Dynasthe piein to poterion ho ego pino e to baptisma ho ego baptizomai baptisthenai.
The American Bible Union Version here has: "Are ye able to drink the cup that I drink, or to endure the immersion which I endure?" This is not as severe as Joseph B. Rotherham's version which has “with the immersion with which I am to be immersed, can ye be immersed? The Emphatic Diaglott's Greek word for word translation has "and the dipping, which I am dipped to be dipped." (See also Worrell's New Testament, the New Testament translated from the Purest Greek by John Bowes & The New Testament Translated from the Original Greek by H. T. Anderson)
Unlike the Common Version (King James Authorized version), The American Bible Union version uses JEHOVAH faithfully instead of the traditional replacement of LORD in the Old Testament. It is also interesting to note where the translators departed from the Greek Text of the Common Version (the Received Text). 1 John 5:7, 8 removes the wording "For there are three that bear record in heaven, the Father, the Word, and the Holy Ghost: and these three are one" with a note saying "The words omitted are wanting in all ancient copies." However, 1 Timothy 3:16 still uses "God was manifested in the flesh" with a note this time saying, "In ancient copies: who was manifested."