Mentions bone-piece jewellery common in Viking Dublin- Used for variety of functions such as hairpin, clothes pin etc. Relatively small in size, reference to size by bones mentioned by Heaney "jaw-bone" or "rib".
Heaney guessing its purpose "it could.".
Stanza Two~.
"Small outline was incised" meaning a shape or picture carved/scratched into the bone. Highly decorated heads on all of bone pins etc. "Trellis" and "cage" imagery playing on idea of bone and therefore skeleton "ribs" previously mentioned, cage-like in shape.
"To conjure in" has idea of using imagination to bring up images and ideas about the Viking's past. Magic element of "conjure" has sense of amazement about what one small piece of bone can teach about life in Viking Dublin.
"Like a child's tongue"- Similie// Suggests a sense of learning as a child does with their tongue (what is nice, what burns etc) Path of discovery.
"Following the toils" following the troubles, could be seen as troubles of discovering, or troubles of the Vikings reflected in the carvings.
Stanza Three~.
"Like an Eel swallowed in a basket of eels" Another Similie. Significance of one trial piece is overlooked because of other things that have been found. Importance of such a small object overlooked. .
-Could also be seen as past/heritage lost with passing of time. Viking heritage is gradually lost.
FISHING ANALOGY- "eel" "the line" "bill" "swimming" "netted".
-reference to importance of water in Viking's lives.
Stanza Four~.
Fishing analogy, with "line" could be seen as fishing for clues and knowledge. The "hand who fed it" being the Vikings from the past, or more specifically, the Viking who carved the bone.
"Amazes"- personification (gives living characteristics to objects) so amazing that it small bone piece has outlasted the Vikings in Ireland. .
"Swimming Nostril" more personification "nostril" maybe describing the pattern on the bone. Swirls and circles common patterns in decorative Viking jewellery.