In Isa 34:7, the KJV translates the passage as follows:
And the unicorns shall come down with them, and the bullocks with the bulls; and their land shall be soaked with blood, and their dust made fat with fatness.
The JST, however, reads thusly:
And the reem shall come down with them, and the bullocks with the bulls; and their land shall be soaked with blood, and their dust made fat with fatness.
The Hebrew term translated as "unicorn" in the KJV is רְאֵם and while meaning is still not completely known (per HALOT and other sources), most modern translations render the term as "oxen" (e.g., NRSV).
What is rather interesting is that, as has been noted by Thomas Wayment and others, this is further evidence that the JST is dependent upon Adam Clarke’s commentaries.
In Clarke's commentary on Isaiah 34:7, we read the following:
The unicorns shall come down - ראמים reemim, translated wild goats by Bishop Lowth. The ראם reem Bochart thinks to be a species of wild goat in the deserts of Arabia. It seems generally to mean the rhinoceros.
One will note that Clarke transliterates as the Hebrew as reem (reemim is also used as the Hebrew is in the plural in this verse).
Interestingly, as with Joseph Smith, Clarke did call into question the worth of the Song of Solomon:
Let us for a moment consider the different opinions held on this book, without entering into the discussion of their propriety or impropriety. They are the following:--
I. it is a plain epithalamium on the marriage of Solomon with the daughter of Pharaoh, king of Egypt; and is to be understood in no other way.
II. It is an allegory relative to the conduct of God towards the Hebrews, in bringing them out of Egypt through the wilderness to the Promised Land.
III. It is intended to represent the incarnation of Jesus Christ, or his marriage with human nature, in reference to its redemption.
IV. It represents Christ's love to the Church or elected souls, and their love to him.
V. It is an allegorical poem on the glories of Jesus Christ and the Virgin Mary.
VI. it is a collection of sacred idyls; the spiritual meaning of which is not agreed on.
Now each of these opinions has its powerful supports, and each of these has reasons to offer for the support of the opinion which is espoused; and nothing but a direct revelation from God can show us which of these opinions is the correct one, or whether any of them are correct . . . To conclude: I advise all young ministers to avoid preaching on Solomon's Song. If they take a text out of it, to proclaim salvation to lost sinners, they must borrow their doctrines from other portions of Scripture, where all is plain and pointed. And why then leave such, and go out of their way to find allegorical meanings, taking a whole book by storm, and leaving the word of God to serve tables? (The Holy Bible Containing the Old and New Testaments: The Text Carefully Printed from the Most Correct Copies of the Present Authorized Translation Including the Marginal Readings and Parallel Texts with a Commentary and Critical Notes Designed as a Help to a Better Understanding of the Sacred Writings, Volume 3, pp. 842, 849)
