The experimental account of the advantages of the curved wing and the attempt to interpret the results through streamlines. The disassemble of the resultant air force in its lift and drag components. The development and use of very simple measuring instruments, which supplied among other things the first actual available measurements of ratio and direction of the resultant air force. This was successful because of the largeness of the apparatuses through which some measuring mistakes became irrelevant. Most important measuring instruments were different whirling arm apparatuses and air force measuring instruments for natural wind.
Reconstructions are in the museum.