Update.
For those who are interested in older issues of Barbour's magazine, the folks over at http://truthhistory.blogspot.com/
are making a PDF available of an early issue of The Midnight Cry and the Herald of the Morning. It's the January 1874 issue which has never before been public to researchers. Issues of this magazine are very significant in understanding the influences and history of the Barbour/Russell movement. It was issues of this magazine which Charles Taze Russell read in 1875/6 which led to his accepting the idea of an invisible presence of Christ in 1874 and the 1874-1914 chronology.
Information on how to obtain a PDF copy of this issue can be found at:
http://truthhistory.blogspot.com/2009/08/herald-of-morning.html
Contributions for the PDF will be used by these researchers to provide more photocopies of other older Watchtower related publications. It's a worthy cause.
Perhaps later more issues of The Herald of the Morning will surface.