10 
of gravitation; to weigh the invisible air and to note the 
delicate organism of microscopic animalculse. 
The navigator, the engineer, the chemist, arc alike indebted 
to him; while on the other hand, the useful arts would stand 
still, the mechanic be no more than the primitive artificer 
were it not for the successive substitutions or additions of 
forces, economical or supplementary, to construct which 
genius informs him; and his hand would be confined to the 
repetition of that labour which has no excitement of novelty 
and is unrelieved by the prospect of improvement. 
Thus Science claims Art as its handmaiden; Ai*t reverences 
Science as her preceptor; each knit to the other with a bene" 
volent sympathy. 
In seeking to acquire an intimacy wdth the secrets of either* 
even in the seemingly motiveless or injudicious study of 
them, some collateral or accidental good may be expected, 
W'hile from the neglect or unwise disregard of them nothing 
can proceed but regret. Although the great truth may lie 
beyond our reach, the honest and pains-taking search for it 
may profit much. Although the investigator may fail to 
reach the ultimate goal of his wishes, he may be entertained 
by many a pleasing diversion on the way. 
Discoveries the most memorable have arisen accidentally ‘ 
and almost unbidden. The stain left on the lips of a dog 
which had feasted on an insignificant shell-fish drew attention 
to that dye* which tinctured the robes kings and conquerors 
were proud to w'ear. We are told that some Phoenician 
sailors, having, for w^ant of other fuel wherewith to cook their 
food on the sea shore, had recourse to some blocks of alkali 
with -which their vessel w'as laden, were astonished to behold 
it, when acted on by heat, dissolve into translucent streams, 
and assume with the sand the undesigned form of vitrification; 
gi\'ing the first hints for the manufacture of glass, now so 
indispensable an article of use, ornament, and luxuiy. The 
‘ Purple. 
“ Tyrioque ardebat murice Icena 
- iiiiicuai 
Domiwa ex humeris. (i, e. of the Pius -2Eneas ) 
ViRO. IV. 26S. 
