▁years ▁he ▁worked ▁as ▁a ▁tile - maker , ▁and ▁devoted ▁himself ▁to ▁the ▁an arch ist ▁movement . ▁ ▁Pe ir ats ▁came ▁to ▁an arch ism ▁after ▁moving ▁in ▁his ▁early ▁years ▁to ▁Barcelona . ▁He ▁was ▁a ▁long - standing ▁member ▁of ▁the ▁Conf ed era ción ▁Nacional ▁del ▁Tra b ajo ▁( CN T ) ▁and ▁at ▁one ▁point ▁edited ▁its ▁newspaper , ▁Sol id ar idad ▁O br era ▁(' Work ers ▁Sol id ar ity '). ▁He ▁was ▁also ▁a ▁member ▁of ▁the ▁feder ation ▁of ▁an arch ist ▁aff inity ▁groups , ▁the ▁Fed era ción ▁An arqu ista ▁Ib érica ▁( FA I ). ▁ ▁As ▁a ▁historian ▁of ▁the ▁Spanish ▁an arch ist ▁movement , ▁Pe ir ats ▁produced ▁an ▁important ▁three ▁volume ▁study ▁of ▁the ▁libert arian ▁movement ▁in ▁the ▁Spanish ▁Civil ▁War , ▁La ▁C NT ▁en ▁la ▁revol ución ▁españ ola . ▁A ▁one ▁volume ▁ab rid g ement , ▁An arch ists ▁in ▁the ▁Spanish ▁Revolution ▁was ▁printed ▁by ▁Black ▁and ▁Red . ▁An ▁English ▁translation ▁of ▁the ▁full ▁three - volume ▁work ▁was ▁published ▁by ▁Stuart ▁Christ ie , ▁edited ▁by ▁Chris ▁E al ham . ▁The ▁first ▁two ▁volumes ▁were ▁published ▁in ▁ 2 0 0 1 ▁and ▁ 2 0 0 5 ▁respectively ; ▁the ▁third ▁volume ▁was ▁published ▁in ▁ 2 0 0 6 . ▁ ▁Pe ir ats ▁papers ▁are ▁held ▁by ▁the ▁International ▁Institute ▁of ▁Social ▁History ▁in ▁Amsterdam . ▁ ▁Works ▁An arch