Help in identifying type film used that produced old black white negatives

Most films have identification text along the edges. If you look on the negatives you may see the frame numbers and some text which will identify the film type.

If you are looking at prints instead of the original film negatives then there really isn't any way to identify the specific film that was used to make the print.

"Kodak Safety Film" is a term that Kodak applied to all of their acetate based films for a period of time. The word "Safety" meant that the film was less prone to spontaneous combustion than its predecessor. (Nitrocellulose films) The term appeared on virtually all formats and types of Kodak films for a few decades.

Kodak, Fuji and Ilford and others used a Notch code system to identify their films of all kinds. A series of notches or shapes is printed into the edge of the film, usually with code number as well.

If you know the code number and the notch pattern then you know what film it is, the name of the film, Tri-X for example, may not have been printed, just the codes.

This web search contains many useful links to learn more.

Photos from Ansco Film Notching Identification Code (1948)

Photo from Yumpu.com 1-3. FILM IDENTIFICATION EDGE MARKINGS AND CODE NOTCHES

This sounds like 120 film size. And it's the size you're really interested in I think, not the emulsion type?

Photo shops can scan your negatives for a few pennies per frame. Or you could try a bodge like this:

https://www.popphoto.com/gear/2011/07/how-to-scan-negatives-using-standard-scanners/

What's being an 86 year old woman got to do with learning a new skill? Go, girl!

Assuming that you have 120 negatives and that your goal is to find a negative holder that fits your scanner so that you can scan these negatives, try a Google search for "epson perfection v730 120 negative holders". I see a few aftermarket negative holders on Ebay that claim to work with 120 film.

The size you give, 2 1/2" by 1 5/8" is the "full frame" format for 127 film (not 120 as other answers have claimed -- 120 gives 2 1/4" width by 1 3/4", 2 1/4", or 3 1/4" along the film (also called 6x4.5, 6x6, and 6x9 in centimeters), while 127 gave 1 5/8" width and lengths of 1 1/4", 1 5/8", and 2 1/2" along the film

That said, without any identifying marks other than "Safety Film" we can only tell you the negatives are Kodak, and were made after about 1912 (Kodak introduced Safety Film commercially in that year, and phased it in across various formats over the next couple decades).

The 127 format became very popular during the Great War, when the Vest Pocket camera line was carried to the front by a large number of American doughboys. These compact strut-folder cameras gave high quality images, but could be stowed away to go places they officially weren't permitted, and as a result, provided much of the record we have of the real conditions at the front during the First World War.