From Wall's Dictionary of Photography 16th ed c1943:
"Most makers of film offer films of four different types,two orthochromatic and two panchromatic.The first two are the ordinary or standard film speed of about 25 degrees Scheiner....and the chrome film of about double the speed of the ordinary film.....they are known as chrome films....Verichrome,Isochrom,Selochrome etc.Of the panchromatic films one,in most makes sold as a fine grain film, has a speed that is usually between that of the chrome and ordinary films, while the speed of the other is usually about double that of the chrome film."
The table converts degrees Scheiner to ASA, my guess that it is old ASA,not sure on this.Scheiner is very likely 25 European, it is a UK book.