What Christian Lamb's important and enlightening book illustrated is that the new botanic gardens were the heartbeat of an empire. The plant hunters and the administrative colleauges should be seen as not eccentric adventurers - no, the proper context if one were to draw a parallel with the present day would be wuth the giants of silicon valley - such as Bill Gates, Steve Jobs and so on.
No group of people in history so transformed the economic, political and cultural landscape as the plant hunters and the great botanical gardens that acted as the hubs and planners for this great pursuit. Imagine a world without industrial amounts of rubber, quinine, tea, coffee, cocoa, spices and so on and without the great corporations and financial institutions that evolved on the back of them and you see a very different world.
These men literally created the foundations for global markets and historically the tragedy of their legacy is that their real importance is overshadowed by the mythology of exploration. The real genius lay in the organising of their discoveries into industrial packages that would shake the world we know today.