In 1916, Thomas Thomson, an engineer living at No. 10 Victoria Street in London, obtained a British patent for a device for digging tunnel holes underground. During the First World War, engineers were looking for a machine that would break up enemy troops. Mr Thomson was also busy looking for such a machine. The pneumatic earth piercer, of Mr Thomson's design, was to be used to lay mines or destroy enemy earth fortifications. However, there is no evidence of military use of Mr Thomson's machine. After 40 years, in 1956, the pneumatic punch appeared in Poland, in the form of an improved design by Mr. Ziemkiewicz. Two years later the inventor received a patent for his improved version.
[001] - The Mole - prototype model from 1956.
A Mole is an instrument that works on the principle of a self-propelled pneumatic hammer. The linear movement of the hammer head is caused by the hammer hitting the anvil located at the front of the body. The reaction of the recoil in the opposite direction is counterbalanced by the friction force that arises between the body and the ground. Thanks to its special design, the recoil is low, so that the device can advance even in light soils. When piercing, the Mole does not throw the soil backwards, but rams it in front of itself and pushes it sideways. Moving in a reciprocating motion, the rammer makes impacts approximately 400 times per minute. The device is powered by compressed air, pressure 6 bar, at a consumption of about 2 m3 per minute. It is ideal for pulling underground electrical and telephone cables, gas pipes, water pipes and ventilation ducts. Thanks to the mole, you can avoid heavy and complicated works, such as ripping out asphalt from roads or runways, digging trenches under railway or tram tracks. It is not necessary to stop traffic to allow digging. 
[002] - The mole - model 100NC. The first Mole from 1956 was a prototype machine, unreliable in its operation - it got stuck in the ground and deviated from a straight line. Thanks to the help of scientists from the Gdańsk University of Technology that the design could be improved and the "childhood diseases" eliminated. This is how the Mole KZ 88 was created and soon production began - many thousands were produced, mainly for export. One of the significant limitations of the "Mole" was its relatively small bore diameter - 88mm. Another limitation was the difficulty in extracting the head. To pull it out, a rope winch had to be used. To eliminate these inconveniences, the device was redesigned. From now on, special cones could be placed on the body. These increased the piercing diameter. If the device got stuck, pulling out was much easier - the main problems were eliminated. 
[003] - A tunnel excavated by pneumatic mole.
The Mole has gained recognition in many countries around the world. The American company Schramm from Pennsylvania, bought the licence to produce the device. Soon the first "Gopher" (this is how the device was named in the USA) was delivered to an American customer. This somewhat forgotten device is still a cheap and good way of digging small holes, both horizontal and vertical. Many modern machines use solutions that once worked successfully with this little-known pneumatic device. • • •
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