Aloe ferox (Cultivated- USA)

Native to: Cape Provinces, Free State, Lesotho; Introduced into: France as per POWO;

Aloe Species seen in the Desert House, at the Conservatory.
Seen during my visit in October, 2018.

The plants in that collection come from Madagascar and the southern part of Africa.
You can please look at Aloe aculeata, A. aristata and A. ferox
There are some others but since I cannot judge the size of your plant, that's a start.
Hope this is somewhat helpful.
Many thanks … for looking into this post.
Thanks a lot for the suggested ids.
I will go through and get back to you

As far as I can remember, it was fairly a large plant. At least two feet, could be more. 
From the suggested ids, Aloe aculeata and Aloe ferox could be possibilities. 
Unfortunately, the garden doesn't have a website with the names and pictures of the plants. It would have been so much easier. 
Attachments (1) - 4 mb.
Yes. Appears close.
I could find a picture of the Aloe posted on this link.
Seems to be the same in my picture. 
The posted link will help you determine the size of the plant.