Sketch of Dr. John Locke. — Winchell. 353 
stone at Cincinnati. With the exception of this error, he out- 
lined the geology of the northern peninsula of Michigan 
eastward from Keweenaw bay. If his full report on this ex- 
amination had been completed and published it certainly 
would have constituted an important chapter in the progres- 
sive development of the geology of that state. 
This, apparently, was Dr. Locke's last geological work. The 
study of magnetism and the increasing exactions of his pro- 
fessorship at Cincinnati engrossed all his attention. 
Personallj 7 , Dr. Locke was slightly above medium hight. 
From his feet to his eyes, as stated by himself in explaining 
the use of his "level," he measured 5 feet 5 inches. He was 
not physicall} 7 rugged ; his countenance had usually the sickly, 
almost sad. expression of a severe student. He was indifferent 
to exposure, either of cold or rain, and never carried an um- 
brella. "When involved with some problem of physics it was 
his habit to give himself no rest. His nervous excitement sus- 
tained his physical powers with little aid from sleep. Pros- 
tration usually followed, but he was soon at his work again. 
This habit doubtless permanently injured him both mentally 
and physicall} T , for his death at 64 years was described as due 
to "'a breaking up, as it were, of the great nervous centers." 
In manner he was marked hy the dignity of his address and 
the courtliness which partook of the old regime of the eigh- 
teenth centur} T . He was a man of fine presence, with an open 
and benignant countenance, in all respects a rare specimen of 
cultured manhood. In Ohio his home was for some time at 
Lebanon, the horne of Tom Corwin, and they became firm 
friends. Locke, Corwin and Thomas Ewing, the last the 
father of Mrs. Gen. W. T. Sherman, were very close friends, 
making a notable trio. It was at Corwtn's instance that Con- 
gress purchased Dr. Locke's electro-chronograph. 
Dr. Locke married Mary Morris, of Newark, N. J., in isj.~>. 
She had been one of his pupils. She was a most estimable 
lady and his domestic life was a very happy one. They reared 
a large and interesting family, but one son died young and 
two in early manhood. 
Dr. Locke's career, from first to last, was a remarkable one. 
Single handed, as a youth, be attacked the outworks of a great 
problem the issue of which was. to say the least, precarioui 
