How old is cable company piano seial number 278834?

Unless the serial number sequence was different on the Chicago models and the W.H. Palings models sold in Australia (that is, if there was only one sequence of serial numbers for all Victor pianos), yours probably dates to the early 1900's.

Serial # 52000was manufactured in 1925 and serial # 40004, about 1870.

Some information, much of it conflicting, indicates that your piano was manufactured in 1921.

I wonder if it is quite tall and has two candle holders, just to see if we are talking about the same manufacturer.