348 The American Geologist. December, 1894 
sists of magnetical and barometrical observations, a catalogue 
of specimens collected, and daily journal from July 8, 1847, to 
August 30, the last mentioned evidently kept by some member 
of his part}'. It appears from this journal that I)r. Locke, 
after making a reconnoissance southward from lake .Superior to 
the waters of the Escanaba river which enters little Bay de 
Noquet, returned to lake Superior, and thence, on his way to 
lake Michigan to make connection by way of little Bay de 
Noquet, made a detour into Canada, visiting the region of 
Bruce mines and Echo lake, and subsequently noted the geology 
of the shores of Drummond's island. Of the geology of this 
season's work, on which he was engaged in making a full re- 
port, with maps, Jan. 23, 1848,* date of his letter transmitting 
his magnetical observations, there is no report in Jackson's 
final report. Of this Dr. Jackson says: 
1 have sent Dr. John Locke's reporl on magnetic observations, and have 
requested him to send in some additional matter on the subject, and 
also his notes or report on the geology of the district which I assigned to 
him in 1847. His occupations in another service of the country during 
the past year have prevented his completing his geological report in sea- 
son to forward to me, but I trust it will be communicated to you in sea 
son to be printed in my report. 
In 1848 Dr. Locke 
"was detached, by orders of the Secretary of the Treasury, as a mag- 
netic surveyor, in accordance with my request, and a vacancy thus 
made in the assistants" corps was filled by my promotion of Mr. J. Ay. 
Foster to tlic place of assistant geologist." (p. 379.) 
Dr. Jackson also says (p. 424) : 
"Dr. John Locke lias been detached at his own request, and by the 
advice of the honorable Secretary of the Treasury, to make magnetic 
observations on both Dr. Owen's district and mine; but owing to the 
lateness of the passanv of the appropriation bill, did not enter upon field 
duties this year. The appropriation bill not passing till August, it was 
considered then to be too late for the beginning of Dr. Locke's field 
duties, and tin' means placed at the disposal of Dr. Owen and myself 
were not sufficient to maintain that survey until the appropriation 
should lie placed at our disposal. This was a matter of regret, for the 
magnetic observations had already begun to yield interesting results." 
Dr. Locke does not seem to have returned to the survey 
under Dr. Owen, nor indeed to have been again actively en- 
gaged in the geology of the Northwest. He was doubtless 
deepl} T involved in his magnetic studies, to which Dr. Jackson 
-Jackson's report, p. 556. 
