He undertook modest little excursions into the woods or along the margin of the lake, sometimes alone, but more frequently with a little friend whose whole heart and being seemed to be swallowed up in admiration of his big companion.

Whether Crusoe botanized or geologized on these excursions we will not venture to say.

Assuredly he seemed as though he did both, for he poked his nose into every bush and tuft of moss, and turned over the stones, and dug holes in the ground--and, in short, if he did not understand these sciences, he behaved very much as if he did.

Certainly he knew as much about them as many of the human species do.
In these walks he never took the slightest notice of Grumps (that was the little dog's name), but Grumps made up for this by taking excessive notice of him.

When Crusoe stopped, Grumps stopped and sat down to look at him.