450 FRESH-WATER SHELL-HEAPS 
and his inventions have been progressively developed, and _ 
analogy, as we think, legitimately suggests that the most — 
simple inventions are signs of actual progress, and point — 
back to an earlier state out of which he has emerged. The 
discovery of the oldest of man’s works, either iu the form 
of worked flints, earthen vessels, and of fire-hearths, do not 
carry us back to his beginning; if we would attain toa — 
knowledge of this, it must be sought for in the remains of 
his own body, older than all his works. 
We have as yet no data for determining the time or the 7 
order of his inventions. But of all his works thus far dis i 
covered, flint-implements are the most ancient, and earthen 
_ vessels the next. The invention of fire and cookery appears 
to have preceded that of pottery, the proof of the existence 
of the former being the oldest. The determination of how, 
and the period when, fire was first made available as an 
agent, would be one of the most important contributions 
the history of the early progress of the human mind. oe 
The shell-heaps on the St. Johns River, like those from 
the other parts of the United States, show that those who 
inhabited them were not, strictly speaking, primitive men. — 
They had already made some progress in the useful arts, and 
however rude their instruments, these were nevertheless m- 
ventions, and such, too, as could only have been the result of 
experience extending through considerable periods of time. 
They not only used worked stone, bone and shell, but their 
pottery had passed out of the first and rudest stage into that 
of comely forms with outward ornament, and, as the table 
on the opposite page shows, exhibits some little variety ™ 
the composition of the materials. : 
- For the purposes of comparison we have included in the 
enumeration, articles obtained from St. Johns Bluff, bee 
the shell-heap is made up of salt-water species. The table 
shows that more than three-fourths, eighty per cent., of : 
the pieces were made of clay without the admixture of anys 
" other substance, and that when another substance was adde® 


