I thought this was nice
The Rd number is for end of 1891
Any item displaying a Registered number or design..which was common practice for most manufactured items..can be researched online..plenty of sites display the chronological design numbers and date charts which can be looked up...I use them all the time..simples.
Heres another 1742 + 150 years = 1892
Probably cos someone has got their dates wrong