Hi,
According to my research for my book on the Gainesville Midland Railroad, I examined the actual photo of the same train before it departed Gainesville. Using a magnifying glass, the locomotive is 2-6-0 #16, the coach is number 3 (seated 48), and the combine is a number in the teens. The first digit is "1" but the second digit was indeterminate as the banner covered most of it.
Oddly enough, I was never able to find details on GM #16. The only hint was that it might have been ex-Florida Southern (of maybe South Florida) #16.
The narrow gauge from Monroe to Gainesville was standard gauged in 1914 and abandoned in 1948.
This same photo (although not as good a reproduction) is in my book. The same train and manner in Talmo is also available in the State of Georgia Archives.
Monroe was a dual gauge transfer point with the Georgia Railroad.
Doug vV