What does "Sadness frowned at him" and "The spider smiled at the fly" means?

The first sentence is a personification and the second sentence is meaning that the spider is hungry and its smiling at the fly. Hope it helps!! 

Sadness frowned at him is basically saying he was depressed, I believe.The spider smiling at a fly...well thats exactly what it means. the spider litterally smiled at the fly OR showed the fly his fangs