Antique Table with Wrought Iron Designs

This desk/table has metal (iron?) knobs and  intericate iron designs between the legs.  We found the initials MJL etched into the wooden back panel of the table but it doesn't look like it was "sketched" in when it was made. 

There are letters that we cannot make out in the curved metal portions that we cannot make out clearly enough.  We see a letter "R" somewhat but that's about all we can make out.  

I would like to know more about this table (what period, what type of wood it may be, value, care).  So far we have lightly sanded the table to clean and even it out but we would like to know what can be applied to protect the wood and what can be used to clean the iron to clean it up and perhaps make out more of the lettering.  

Any input will be appreciated!