Two parts to your question: why send a dredge; and, why send it when it takes so long.

1. The book says to map zone boundaries (not quoting). james-sheridan mentions some others.

2. Examples of people investing for a return after their death: corporate planning (nb: it is reflected in their stock price, today); religions (the catholic church surely take a long-term view with respect to their real estate); government (national parks were created for future generations, and was reflected in votes for candidates, at that time; there's also water resource planning, channel dredging, metropolitan zoning (heh) expansion planning, electricity sourcing); and of course for one's descendants (e.g. trust funds).

I guess dredges are closest to mapping/survey/exploration expeditions. While those in the past few centuries only took years, not life-times, in a sense, they did take a life-time: the people authorizing/funding voyage (king, queen, government official) really might not be alive upon return... and for an official, might not still have that job - especially for an elected official.

A relevant example is JFK, who never saw the moon landings.

Two parts to your question: why send a dredge; and, why send it when it takes so long.

1. The book says to map zone boundaries (not quoting). james-sheridan mentions some others.

2. Examples of people investing for a return after their death: corporate planning (nb: it is reflected in their stock price, today); religions (the catholic church surely take a long-term view with respect to their real estate); government (national parks were created for future generations, and was reflected in votes for candidates, at that time; there's also water resource planning, channel dredging, metropolitan zoning (heh) expansion planning, electricity sourcing); and of course for one's descendants (e.g. trust funds).

I guess dredges are closest to mapping/survey/exploration expeditions. While those in the past few centuries only took years, not life-times, in a sense, they did take a life-time: the people authorizing/funding voyage (king, queen, government official) really might not be alive upon return... and for an official, might not still have that job - especially for an elected official.

A relevant example is JFK, who never saw the moon landings.