Question

After earning a few dollars working on my brother-in law's farm near Portage [Wisconsin], I set off on the first of my long lonely excursions, botanising in glorious freedom around the Great Lakes and wandering through innumerable tamarac and arbor-vitae swamps, and forests of maple, basswood, ash, elm, balsam, fir, pine, spruce, hemlock, rejoicing in their bound wealth and strength and beauty, climbing the trees, revelling in their flowers and fruit like bees in beds of goldenrods, glorying in the fresh cool beauty and charm of the bog and meadow heathworts, grasses, carices, ferns, mosses, liverworts displayed in boundless profusion.
CHOOSE TWO OF THE FOLLOWING PHRASES MUIR USES IN HIS WRITING ABOUT THE CALYPSO BOREALIS. IN TWO TO THREE SENTENCES, EXPLAIN HOW THESE WORDS REVEAL HIS ATTITUDE TOWARD NATURE.

botanising in glorious freedom

rejoicing in their bound wealth and strength and beauty

revelling in their flowers and fruit like bees in beds of goldenrods

glorying in the fresh cool beauty and charm of the bog

Answer 1

1)
Botanising in glorious freedom because he is telling how very excited he is to be free from the farm as well as very interested in the plant life that is where he is now. 
2)
Rejoicing in their bound wealth and strength and beauty, because he is expressing how he feels about them how he thinks they are strong and beautiful, how he is very happy about the way they are.
                        ....................Hope it helps, Have a good rest of the day:)