You can see part of it in your photo of Jacob's grave, but attached here is a better photo of her gravestone to the immediate left of his in the Jacksonville Cemetery in Oregon. The photo was taken by a woman named Teri Sutton and uploaded to Pinterest on Halloween, 2011 at this website:
http://pinterest.com/pin/415070292/J. Ellen
Beloved Wife of Jacob Ish
born Oct 12 1825
died July 28 1877
The photo is excellent, deep blue sky, good contrast on the lettering, nice and clear. There's a religious inscription on the bottom somewhat obscured by the fence: ".... in God's own morn ... orb ....." This was a traditional inscription on graves of that era, and with a little research, I puzzled it out:
MY MOTHER:
In God's own morn / her orb will rise
once more a star / of Paradise
I am no relation to the ISH family; this was a RAOGK. :)