"I rolled a ball along the street from the police station to the second traffic lights?"
Let's make it clear that along
is a preposition(前置詞) in this sentence, not an adverb(副詞).
"rolling along the street (道を転がる)"
rolling along the street
would be better translated as 「道に沿って転がる」 rather than 「道を転がる」. 「道を転がる」 is a shorter version of 「道の上を転がる」. So it means "rolling onto the street".
And with this phrase, the subject is a thing that actually rolls by itself such as a ball. (e.g. The ball rolled along the street.) On the other hand, the subject of 「ボールを転がす」 is not a ball but a person or a kind of force that rolls the ball. (e.g. The wind/I rolled the ball.)
「転がる」 and 「転がす」 are different kind of verbs. The former is an intransitive verb(自動詞) which does not require an object(目的語). On the other hand, the latter is a transitive verb(他動詞) and requires an object(目的語).
So "道をボールを転がす", which sounds really odd to the natives, appears that "ボールが道の上を転がる" and "私がボールを転がす" are said at once in one clause of a sentence.
I want to capture the movement along the direction of the street and we can't have two をs
" What do you mean?on
the surface of the street." Ifonto
implies there is a connection between the current and the previous position, then simplyon
should be it. To think it as free translation, I don't see a problem to say「道の上を転がる」
meansrolling along the surface of the street
. However, if it needs to be more precise and catch the literal meaning of 「の上を」, I would avoid includingalong
in the translation since 「上」 does not have a meaning of along.