Recently I purchased a country house in rural America. I am from California needless to say rural America is more lax then California.

I have 2 120v mercury vapor lights in my yard. I trace the wires down (Via Aerial) and the go right to main service disconnect. I have also seen people out here taping into their aerial drops (after the main service disconnect) to connect small 60 amp breaker panels. In both is this common practice and is it safe?

Actually it is fairly common to go to a main disconnect, then branch off from there to the main house with one line, to a barn with a another, etc. in rural installations.

Not saying every installation is exactly perfect, at least there is the main disconnect to provide short circuit protection for the lights you have. You may want to consider installing some sort of fuses or breaker for these lights, if one shorts out the main will trip.

Hello Chris.

As long as each is done with the proper size wire for the application and are mounted properly they will be fine.

Hello in rural america those large outside lights that look like street lights are normally rented, and you will be billed ( or should be billed) a small amount each month for their use. The electric company actually owns them you do not, you merely rent them.

I pay about 6 dollars a month per light for the ones I have, they are connected before the meter normally