How old were they?

The great German-American physicist, Albert Einstein, is generally given credit for realising that the passage of time is not a fixed property of our universe. But I believe that there may be evidence of a prior Welsh discovery that time passing can be perceived differently by different observers.

Consider these data taken from the Census Forms completed by the residents of 64 Vale Road, Rhyl.

Name	Age at Census
	1901	1911
Jane Davies	55	60
John Davies	29	36
Susy Davies	33	40
Maggie Davies	7	16
Jennie Davies	7 months	10

Perhaps the most basic statement of the principle of special relativity should be — the older you are, bach, the more slowly you age.