The online Beagle library now allows anyone to see the amazing range of visual imagery that Darwin poured over during the voyage. See the illustrations here Humboldt's illustration of his famous ascent of Mount Chimborazo in the Andes in 1802.
And it may be our busy lifestyle that keeps us from napping. While naps do not necessarily make up for inadequate or poor quality nighttime sleep, a short nap of 20-30 minutes can help to improve mood, alertness and performance.
1 Exercising for 10-15 minutes can be a great way to take a break while giving yourself even more energy to get your work done. 2  Take a 15-20 minute power nap if you need to. 3  Napping for this short amount of time is better for helping you regain your energy than napping for 1-2 hours, which will only make you feel groggy.