I wander thro' each charter'd street,
Near where the chartered Thames does flow.
And mark in every face I meet
Marks of weakness, marks of woe.
In every cry of every man,
In every Infant's cry of fear,
In every voice: in every ban,
The mind-forged manacles I hear.
How the Chimney-sweeper's cry
Every blackning church appalls;
And the hapless Soldier's sigh
A striking line, the most important in the poem perhaps, appearing exactly half-way through. The previously described trials of the oppressed population make Blake aware of the systems of control – religious, social, economic, political and monarchical – which keep the people in a state of  sufferation . The compressed compound adjective ‘mind-forged’ is especially memorable, with ‘mind’ a  noun modifier  for ‘forged’.  Note also the long vowels which make the line difficult to say — almost a tongue-twister — expressing the mental restrictions it describes. 
 The use of “mind-forged” is important in understanding this poem, as Blake uses it to emphasise the point that these manacles, while a direct result of religious, social, economic, and political forms of control, are also perpetuated by our own limitations. In other words, we create our own internal mental prisons. 
 The “mind-forged manacles” may also be a reference to  Rousseau’s comment  “Man was born free and everywhere he is in chains”. Rouseau was a near contemporary of Blake.
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