most ▁half ▁of ▁the ▁available ▁land ▁was ▁covered ▁with ▁v ine y ards . ▁Agricult ure ▁occupied ▁a ▁further ▁quarter ▁of ▁the ▁land ▁and ▁past ure ▁made ▁up ▁around ▁one ▁fifth . ▁ ▁The ▁Z acher l ▁insect ic ide ▁factory ▁in ▁the ▁N uß wald g asse ▁developed ▁into ▁Unter d ö bling ' s ▁most ▁important ▁industrial ▁enter prise . ▁Johann ▁Z acher l ▁had ▁been ▁importing ▁insect ic ide ▁made ▁of ▁py re th rum ▁from ▁T if lis ▁since ▁ 1 8 4 2 , ▁and ▁in ▁ 1 8 7 0 , ▁he ▁began ▁production ▁in ▁Unter d ö bling . ▁His ▁Z acher lin ▁product ▁was ▁sold ▁in ▁his ▁own ▁sh ops ▁all ▁over ▁the ▁world . ▁Karl ▁May re der ’ s ▁reconst ruction ▁of ▁the ▁factory ▁in ▁the ▁form ▁of ▁a ▁mos que ▁gave ▁Unter d ö bling ▁the ▁most ▁unusual ▁factory ▁building ▁in ▁all ▁of ▁Vienna . ▁Z acher l ’ s ▁he irs ▁strugg led ▁with ▁the ▁growth ▁of ▁the ▁chemical ▁industry ▁after ▁World ▁War ▁I ; ▁in ▁ 1 9 3 3 , ▁they ▁were ▁also ▁producing ▁ski ▁bind ings . ▁The ▁Z acher l ▁factory ▁closed ▁in ▁the ▁ 1 9 5 0 s . ▁ ▁S ights ▁▁ ▁Johann ▁Z acher l ’ s ▁Z acher l fab rik , ▁designed ▁in ▁an ▁orient al ▁style ▁and ▁res emb ling ▁a ▁mos que , ▁is ▁a ▁unique ▁construction . ▁Another ▁important ▁building ▁is ▁the ▁D ö bling ▁Car mel ite