Historic Newspapers Online
Ancestry.com has quite a collection of newspapers digitized online, available by subscription only. However, many libraries subscribe, so you may not need your own subscription. I believe these are fully searchable text. Here's an example, from the "Ancestry Weekly Digest," Sat, 14 May 2005.
From the "Morning Herald" (Titusville, Pa.), 11 May 1869, page 2:
Chicago, May 10
...
THE PACIFIC RAILROAD CELEBRATION.
The celebration of the opening of the Pacific Railroad, which is to take
place to-day, promises to be a grand affair. The weather is all that
could be desired.
LATER.
The celebration of the completion of the great inter-oceanic railway
connection to-day was the most successful affair of the kind that ever
took place in Chicago, and probably in the West. It was entirely
impromptu, and therefore almost every man, woman and child in the city
did their part towards making it a success. Vice President Colfax
received the following dispatch:
Promontory Hill, Utah, May 10.
To Hon. Schuyler Colfax, Vice President:
The rails were connected to-day. The prophecy of Benton to-day is a
fact. "This is the way to India."
[Signed] G.M. Dodge, John Duff, Sidney Dillon, J.C. Durand.
This evening Vice President Colfax, Lieut. Governor Bross and others addressed a large audience at Liberary Hall, in which they spoke eloquently of the great era which this day marks in the history of our country. During the evening there was also a general indulgence in fireworks, bon fires, illuminations, &c.
For more information on the Central Pacific Railroad and the joining of the rails at Promontory, Utah, 10 May 1869, see:
Central Pacific Railroad Photographic History Museum
Oral History: Salt Lake Daily Telegraph of May 11th, 1869, The Pacific R.R. Finished (National Parks Service)
Subscribers with access to the Historical Newspapers Collection can view this clipping [online].
[from the R&LHS Newsgroup]