and of a Mineralogical System, hy the late Dr Walker. 91 
though I had observed it but very sparingly, three years before, 
in the Mines at Leadhills My return to the south was by Glen- 
spean, Fort-Augustus, Coryaroch, the country of Badenoch and 
Drumalbin, to Taymouth. 
• In the year 1771, I was again commissioned, in like manner, 
to visit those islands and parts of the Highlands which I could 
not overtake in the former journey. At that time, I entered 
the Highlands by Balquhidder and Strathearn. I examined the 
high mountain of Benmore, and the mines of Tyandrom. In the 
latter, I found nothing uncommon, excepting a beautiful crys- 
talline ore of zinc. I proceeded northwards from that place, 
through the desert country that reaches to Lochaber, and exa- 
mined Bennevis, the liighest mountain in the island. After 
surveying the countries of Upper, Middle, and Nether Lorn, I 
went through all the Lorn Islands, which afford to a mineralo- 
gist much interesting matter of observation. I then travelled 
through the districts of Argyle and Cowal, and finished the jour- 
ney, by an examination of the Isle of Bute and the Cumbrays. 
In these two journeys, I visited every inhabited island of the 
Hebrides, excepting Arran and St Kilda; a still greater num- 
ber of those islands which are not inhabited, and all the Western 
Highland countries, from the Clyde to the Shore of Assynt, col- 
lecting every where all the remarkable minerals that occurred. 
A considerable addition to. my collection of minerals was made 
in the year 1778, in a journey through Stirlingshire, Perthshire, 
Forfarshire, the Mearns, and Aberdeenshire ; and, since that 
year, by an examination, at different times, of West and East 
Lothian, Renfrewshire, and the county of Berwick. 
Such have been the opportunities of forming a collection of 
the minerals of Scotland. At different times also, 1 had occa- 
sion to traverse most of the counties in England, from the Bor- 
der to London, on the east, and from Carlyle to Bristol, on the 
west side of the island ; when I omitted no opportunity of pre- 
serving whatever was remarkable in the mineral kingdom. But 
* It is not generally known, that at one period, small quantities of strontites 
were found, at Lead Hills ; and the fact in the text proves, that to Dr Walker the 
merit is due of having determined mineralogically that Strontites was a new mine- 
ral species. Dr Hope afterwards, by the discovery of the strontitic earth, added to 
the interest of the determination of Dr Walker, and proved that strontites was also 
a new chemical species. 
