Merge libraries

Eagle provides the "Merge Library" function, you can merge the libraries created at different time and scene. 

1. Open the main library (Refer to the library as A library)
2. Click "Library" > "Merge Library"
   
3. Select the library you want to merge(Refer to the library  as B library)
4. Finally, the contents of the A library are A+B library
   

Eagle won't automatically delete the library which was merged. You can decide whether you want to delete it after the merge is complete.