...and he caught Deagol by the throat and strangled him, because the gold looked so bright and beautiful.  Then he put the ring on his finger.

 

...Smeagol returned alone; and he found that none of his family could see him, when he was wearing the ring.  He was very pleased with his discovery and he concealed it; and he used it to find out secrets, and he put his knowledge to crooked and malicious uses.  He bacame sharp-eyed and keen-earned for all that was hurtful.  The ring had given him power according to his stature.