You can use below function:
function displayCostSheetComments() {
$().SPServices({
operation: "GetVersionCollection",
async: true,
strlistID: "yourListName",
strlistItemID: "yourListItemId",
strFieldName: "yourFieldnName",
completefunc: function (xData, Status) {
$(xData.responseText).find("Version").each(function (i) {
var comments = {
User: $(this).attr("Editor").split(",#,#")[1],
Comments: $(this).attr("Comments"),
CommentDate: $(this).attr("Modified")
};
console.log("Name: " + $(this).attr("Editor") + $(this).attr("Comments") + " Modified: " + $(this).attr("Modified"));
});
}
});
}