1 879.3 Ancient Observatory at Delhi . 781 
was divided radially into six divisions by five deep lines, and 
each division into five subdivisions by finer lines. So each 
large division represented io° divided by 6, or — 
100 minutes of azimuth angle ; and consequently each 
finely-marked subdivision equalled 20' of angle. 
I am not able to say positively that these finer subdivisions 
were continued on the vertical walls. I saw some parts 
where the fine cement appeared intaCt, but not within 
reach, where I thought the finer lines apppeared, but I was 
not certain. They did not exist on the index edges, where 
the written numbers of the degrees were marked. The 
inner ends of the sectors were much damaged, the open 
space between them and the centre pillar being anything 
from 6 to 8 feet. 
The centre pillar has a ring of well-cut stones* eighteen 
in number, on a level with and corresponding to the 
eighteen sectors. They are of the fine red freestone of the 
district, and project from the pillar about 2 inches (not ex- 
actly recorded in my notes). Their upper surface is level 
and finely dressed, and divided equally by radial lines into 
six parts. The space between each stone — equal in width 
to the stone itself-— is occupied by a red stripe running ver- 
tically the whole length of the pillar. The pillar itself is 
divided above the level of the projecting stones, by clearly- 
marked red rings, into five horizontal blocks, each block 
being subdivided by finer horizontal lines into nine smaller 
blocks. 
Judgingby eye, and with the assistance of my Lieutenant 
on the opposite side of the tower, it was clear that the 
middle of each of the bolder red rings was intended to be 
(and indeed was) on the same level as the 36°, 27°, &c., 
marked on the index edges of the observing recesses. And 
the marks were as closely accurate as we were capable of 
discerning with the unaided eye. The level stone on the 
summit of each central pillar was in its place, with the edge 
angle very fine dressed. 
In the northern tower, which is the one nearest the Sun- 
dial, the prolongation of the gnomon’s western face is 
marked by a window, unlike the others in the tower. It is 
of lancet-shape, but extends from second to third row of 
windows counting from the ground ; its apex marks the 
prolongation of the north and south line, while the same 
line on the opposite side of the tower falls exactly on the 
