114 AUDUBON, THE NATURALIST 
ceeded Miers Fisher as Jean Audubon’s agent, and 
becoming enthusiastic over the lead mine, was anxious to 
exploit it. Acting also upon the senior Audubon’s re- 
quest, he assumed a sort of guardianship over the son. 
Dacosta began to dig for ore in the following year. 
News of his enterprise spread rapidly, and this long 
neglected mine was heralded in the newspapers as “one 
of the first discoveries yet made in the United States.’ 
On December 15, 1804, Dacosta purchased a one-half 
undivided interest in “Mill Grove,’* giving, as we be- 
lieve, a mortgage, and hoping to pay for his share out 
of the profits of the lead mine. Thereafter for about 
two years he continued to conduct the farm and develop 
the mine, upon the basis of a one-half interest, in addi- 
It seems probable that Dacosta was sent to this country by Lieutenant 
Audubon to act as his agent for the disposition of “Mill Grove,” and to 
succeed Miers Fisher in the conduct of his business affairs. Interest in 
the neglected and forgotten mine may have diverted them from their 
original plans. 
?The following notice, copied from Relf’s Gazette, appeared in the 
New York Herald for Saturday, November 17, 1804: 
“The lead mine discovered on Perkiomen creek, in Montgomery county, 
Pennsylvania, the property of Francis Dacosta, has been lately opened, and 
attended with great success. The vein proves to be a regular one, and 
of long continuance. Its course is N.N.E.; its direction is nearly per- 
pendicular, and its thickness from one foot to 15 inches. Two tons of 
that beautiful ore were raised in a few hours, and one ton more at 
least was left in the bottom on the pit, which is yet but nine feet deep. 
From the situation of this mine, its nearness to navigation and market, 
its very commanding height, its richness in metal, and the large scale it 
forms on; it is thought by judges to be one of the first discoveries yet 
made in the U. S. 
“From the analysis made of 100 parts, it contains: 
Oxy.drotileadmarciiaerssisnc cee 85 
Oxy dio fziromy ei isserefeceists sures clcnetereterays 1 
Sulphuric acid: cc... 35eelsneccces 13 
VEG OponinoaunnhonddcomicodggdubbuoS 1 
100 
“The lead being coupelled, has proved to contain 21% oz. fine silver to 
100, which is nearly 3 dollars worth of that metal.” 
* For the sum of 31,000 francs, cr $6,200, a slight advance on the cost 
to Jean Audubon, when he had taken over the farm fifteen years before 
(see Vol. I, p. 105). 
