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Transactions of the Boyal Society of South Africa. 
avenue of error was guarded, and every line of weakness strengthened, 
the Ascension determination of the sun's distance stands unique and 
unchallenged. 
His results were at once accepted by the scientific world as the last 
word on the vexed question of the sun's distance. The boldness and 
originality of his methods of observation, as well as the clearness and 
fearlessness of his ^convictions and conclusions, marked him straightway 
for place and distinction. The gold medal of the Eoyal Astronomical 
Society, its highest award, was bestowed upon him soon after his 
return, and his name became a common note in the astronomical 
world. He was then only thirty-four years of age. 
The value deduced by Gill for the sun's parallax was 
8-78" ± 0-01", 
an amount but little different from that determined at Mauritius. But 
this correspondence is a good deal fortuitous, as the accuracy of the 
Ascension results has more than three times the weight of that 
deduced from the Mauritius observations. 
It was almost thirty years before this value was improved upon, and 
then again by Gill himself. But although ten years passed before another 
determination was entered upon the conditions and essentials of the 
investigation never departed from Gill's mind; and this is fortunate, 
for when again he took up the problem it was with a mind tried, 
prepared, and suitably competent to deal with it. 
On his return from Ascension Gill settled down in London, happy 
in his home, in the society of his many scientific friends, and in the 
occupation of producing work that he knew to be valuable and 
abiding. 
In 1878 his father died, and while in Aberdeen seeing after the affairs 
of his father's estate news reached him of the death of Main, Eadcliffe 
observer at Oxford. Gill, who by this time had severed his connection 
with Dun Echt, at once applied for the post, but was told that it had been 
given to Stone, then Her Majesty's Astronomer at the Cape. Stone 
succeeded Maclear in 1870, but the appointment for the Cape was not 
the happiest possible. Stone had little organizing power, and his indif- 
ferent health stood in the way of his success as an observer. What we 
owe to him, and what no other man could probably do so well, was the 
reduction of the great bulk of Maclear's observations, and the Cape 1880 
Catalogue. He was more fitted for a professor's chair than the manage- 
ment and expanding of a great observatory, and, recognizing this, he 
gladly accepted Oxford when it was offered to him. But as he had not 
completed all the reductions necessary for the 1880 Catalogue, he asked 
that his new appointment be allowed to stand over for a time. 
