![](https://coimages.sciencemuseumgroup.org.uk/4/545/large_thumbnail_1878_0011__0008_.jpg)
Photographic enlargement showing the construction of the 26-inch equatorial refracter for Johannesburg Observatory
One of six photographic enlargements showing the construction of the 26-inch equatorial refracter for Johannesburg Observatory, prepared from negatives lent by Sir Howard Grubb, Parsons and Co.