I took my Power in my Hand — Goliath Beetle

Dickinson went out to study the nature with a magnifying glass. She fell while watching a Goliath beetle. The "power in my hand" is her writing skill. Dickinson was bold but fell before the literature Goliath.

I took my Power in my Hand－1
And went against the World－
'Twas not so much as David－had－
But I－was twice as bold－

I aimed by Pebble－but Myself 5
Was all the one that fell－
Was it Goliath－was too large－
Or was myself－too small?
(F.660/J.540)
[1] Power:: the capacity of a lens for magnifying the apparent size of an object; also elliptical, the lens itself (OED n.1 15).
[3] David:: name of a friend or neighbour; a child later to be a great king.
[5] Pebble:: a lens (OED 2); a person or animal very hard to deal with (OED 1c), indicating Dickinson herself.
[7] Goliath:: Goliath beetle, a very large beetle (OED 2a).

Some of them are of immense size, and have been styled the princes of the beetle tribes; such are the Incas of South America, and the Goliath beetle (Hegemon Goliatus) of Guinea, the latter being more than four inches long, two inches broad, and thick and heavy in proportion. ─ A Report on the Insects of Massachusetts (1841)