The sled dogs would go cross-eyed nuts with excitement just before the sled brake was lifted and they could lunge forward.
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/44124348109@N01">Steve Jurvetson</a> from Menlo Park, USA
CC BY 2.0
<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/44124348109@N01/380256605/">Magic Mush</a>