At this stage Wittgenstein was much more practically minded than one might suppose, given his later highly theoretical work, and he not only studied the theoretical design of the propeller but he actually built and tested it.
Sa hakbang na ito Wittgenstein ay marami pa talaga isip kaysa sa isa maaaring ipagpalagay, na ibinigay ng kanyang mamaya mataas na panteorya trabaho, at siya ay hindi lamang ang panteorya-aral ng disenyo ng elise ngunit siya ang tunay na binuo at nasubok ito.