Hi Michele,
If you go to "Old Maps" and enter Co-ordinate 394353, 806355 you'll see that in 1869 there were 3 lanes running to the left side of Broad Street, and 2 to the right. None of these are named, but presumably one was Raggs Lane.
There were two Poorhouses in Aberdeen, one being the Old Machar Poorhouse (Co-ordinate 393568, 806355), and the St. Nicholas Poorhouse (Co-ordinate 394353, 807148).
Hope this helps.
Bervonian.