The Artizans monograms of 431–487 Harrow Road

I am often bemused and confused as to why the owners of shops within a once beautiful terrace have felt the need to paint their half of the dividing columns. After all the shops would all look more distinct if the dividers were the same thus creating a frame. It just beggars belief why some beautiful patterned and glazed tiles or moulded stonework has been covered over – why can't they just leave them as is?!!!
A couple of months ago I was on one of Jen's walking tours and as we passed a long terrace in Harrow Road I noticed that most of the dividers had been painted through the middle of the initials of a company who either originally built it or traded from within.

It's either AL&CD Company Limited or A&LCD. Note the use of LIM where we now use LTD.

On the northern end of the terrace and in a couple of places high up along the front of the terrace a wonderful monogram using the same letters can be seen.

However I cannot identify the L within these entwined letters. So perhaps it's just "A&CD Co Lim"? In which case what's the significance of the L in the rectangles – a strange ampersandy thing I have never seen before perchance?
As regards researching who this company was I have tried a bit of google-woogle and come up with nothing except a South African Kitchenware company (AL&CD) who don't seem to have ever been in London.
Can anyone help?

Update
Aha!... it's not a C; it's G – turns out it's the Artizans, Labourers & General Dwellings company (interesting that artizans is US spelling but labourers is not)
See the comments for some info/links from Martin