497 
posed to be some modification of that substance. The paper was 
more fully elaborated, and published in the “ Society’s Transac- 
tions” 1793. The German chemist, Klaproth, had also examined 
the Strontian mineral, and without any knowledge of Dr Hope’s 
experiment, had also discovered in it the new earth, and called it 
“ Strontion.” According to our present nomenclature, the earth is 
called Strontia — the metal which forms the basis of the earth is 
Strontium, and was separated and exhibited by Sir Humphrey 
Davy. The native mineral from Strontian which produced the 
earth is called Strontianite, and is a carbonate of Strontia. It has 
been found also at Braundsdorf in Saxony, and elsewhere. There 
ai e other native minerals of which Strontia forms the basis, one 
called Celestine, so named from the beautiful blue tinge of its crystals. 
I have seen lovely specimens of Celestine from the Mountain Lime- 
stone quarries near Bristol. Finer specimens are, however, met with 
in the sulphur mines of Sicily, and still finer in the Strontian island 
in Lake Erie. When it was known that a new earth had been dis- 
covered in the Strontian district, the proprietor and all concerned 
w^ere full of expectations of benefits which might accrue from the 
discovery of a substance of which they were supposed to possess a 
monopoly. But, alas ! no use has been found for it in the arts or 
manufactures — none at least of what may be called particularly bene- 
ficial. The only application has been in the form of nitrate of stron- 
tia, and which is made use of to produce that beautiful red light 
which is exhibited in fire works, and also in certain pantomimic and 
melodramatic effects in theatrical representations, which delight the 
children who attend, both young and old. 
Dr James Robertson, was born in 1803, at Ardlaw, in the parish 
of Old Pitsligo. His father a farmer at Ardlaw, still survives at 
the advanced age of eighty-six. Dr Robertson completed his educa- 
tion at Marischal College, Aberdeen, and his first appointment in 
life was to the parochial school of his native place. He was soon 
after appointed head-master of Gordon’s Hospital in Aberdeen. In 
1832 he was appointed to the living of Ellon, in the gift of the Earl 
of Aberdeen, and was long familiarly known, as a powerful debater 
in the General Assembly, as Robertson of Ellon. In 1843 he was 
called to the Chair of Church History in the University of Edin- 
burgh, and Secretaryship of the Bible Board, and which situations 
