The first series illustrates
the inventions: the horizontal wheel mill, the mining coach from
Brad mine, the fountain pen and the aerodynamic automobile. The
horizontal wheel mill has been considered the “queen of the
artisanal hydrotechnical installations” on the Romanian
territory whose use was mentioned ever since the 13th - 14th
centuries. On a vertical axle there are the ladle-shaped blades
giving the system a supplementary force due to the appearance of a
reactive jet. It was used in the areas where the water fallings had
a low flow. Starting from the constructive principle of the
“horizontal wheel mills”, the American engineer Lester
Allen Pelton invented the turbine which bears his name. The
original exemplars of the horizontal wheel mill may be seen at the
Museum of Masterpieces of Science and Technology in Vienna and
“Dimitrie Leonida” Technical Museum in Bucharest. The
wodden mining coach from Brad - Barza gold mine (16th century) has
been considered as the first vehicle on rails in the history of
technology having a switch. An original exemplar of this coach may
be seen at the Museum of Transports in Berlin and a copy of it may
be seen at the Railway Museum and “Dimitrie Leonida”
Technical Museum in Bucharest. The fountain pen is Petrache
Poenaru’s invention, who, in 1827, obtained in Paris, the
Patent no. 3208 for “the endless self-supplying ink
pen”. The fountain pen invented by Poenaru insures the
accuracy and continuity of writing. The creation of the pen opened
the way for a fast development of the domain of writing instruments
used today all over the world. Petrache Poenaru also stood out as a
remarkable personality in our country’s history. As Nicolae
Iorga said, Poenaru was, in 1821, the editor of Tudor
Vladimirescu’s letters during the months when he was the
“Peasants’ Ruler”. Besides the above mentioned
invention, Poenaru also published the first printed geometry course
in our country, translated the first algebra course and printed,
together with Aaron Florian, the first French-Romanian dictionary
in two volumes. The aerodynamic automobile, invented by Aurel
Persu, was patented in Berlin in 1922, under the name of
“Automobile having an aerodynamic shape with four wheels
mounted inside the aerodynamic coachwork” (German patent no.
402683, November 1922). The engineer Aurel Persu, a specialist in
airplanes aerodynamics and dynamics, was one of the first world
specialists who studied the adaptation of the aerodynamic shape at
the automobiles. After many calculations and lab experiments, he
reached the conclusion that a vehicle coachwork should be shaped as
a falling water-drop. He built it between 1922 and 1923 in Berlin.
Considering the diminished distance between the rear wheels, he
gave up the differential system for the transmission of the engine
torque. The drag coefficient for Persu’s automobile stood at
around 0.28, compared to 0.8-1.0 as the same parameter registered
in all automobiles used at that time. More precisely, the fuel
consumption decreased 4-5 times in the inventor’s automobile.
The automobile, brought to Romania, ran more than 160,000 km. Aurel
Persu donated the automobile fully functional to “Dimitrie
Leonida” Technical Museum.
