It is difficult to begin with this chapter so rich in occurrences. Actually, it's not about one, but about two inventions. In addition, there are other people who are not entirely unimportant for the development of the internal combustion engine and its adaptation in the motor vehicle. It is also not possible to be sure that a sufficient cross-section of those who have been involved in the development of the internal combustion engine has been made so far.

Even more will crawl out of their holes if one starts to doubt the patents after the grandiose success of a technical solution. This later happened to Rudolf Diesel and it was no different with Otto. But still we have a bad feeling because in so many countries there were technical solutions for movement with steam, gas, liquid fuel and electricity. But at some point it has to be, then Nicolaus August Otto has to appear in this book.

If only because of the many corrections that will hopefully no longer be needed then. It's like with James Watt, who is still often claimed to have invented the steam engine. For example, Otto did not really invent the Otto engine. Why? Because today we use the term 'Otto engine' synonymously for a petrol engine. However, we have to state that Otto invented the four-stroke engine, so this principle also exists in a similar quantity in diesel engines.

His first major success was not this, but Lenoir's atmospheric gas motor, which he completely redesigned and helped to achieve a significantly higher degree of efficiency. And yet Otto had not had a technical, but a commercial education. And to top it off, both his first atmospheric and his four-stroke engine ran on gas, not natural gas but coal-derived town gas.

But now one after the other. Nicolaus Otto was born in 1832 in a small town in the Taunus, about 100 km east of Cologne. Whether the father was a farmer, innkeeper or postman or all of them, in any case he died early. Otto left the Realschule in 1848 with a good leaving certificate for the three-year business training course mentioned above.

We see him again in 1861 in Cologne, where he earns his living as a traveling salesman in mail coaches, probably mainly in the Eifel. His mother died a year earlier, leaving him with a small fortune. It is said that his motivation and that of his brother were based on the Lenoir engine invented in 1860.

Basically, one was looking for a gap filler. Because the steam engine, which had long advanced the industrial age, was more worthwhile the greater the need for torque and power. The crafts and small trades had received overwhelming competition from the factories, but could have caught up with a smaller, less cumbersome and also more economical drive.

And if it could have run on liquid fuel and neither boiler nor chimney would need, it could have been used anywhere. Some sources claim that the first patent application, which was rejected by the way, already contained the intention of powering vehicles with such a motor. In any case, the older brother Wilhelm withdrew after the rejection.

The findings came from experience with a kind of Lenoir replica that the mechanic Michael Zons built for him in his workshop. At some point while experimenting with heated spirits, he noticed the enormous increase in power that a burning mixture developed when it was first compressed.

He deputed Zons to build something like a four-stroke engine. Above you can see a reproduction, photographed in the Deutz AG Museum in Cologne. If you take a closer look and analyze it, you may get a little closer to the course of history towards the four-stroke engine.

What we see are four cylinders with the left side pistons near TDC and the right side near BDC. So each side performs the same movements. A comparison with the much later boxer engine is by no means given here.

We omit the 2:1 gear drive because it does not appear in the 1885 sketch from which this model is believed to have been made. Neither original drawings nor the original engine are still present. The gear train could have been added to prove the four-stroke principle.

In his book 'History of German Internal Combustion Engine Construction', Professor Friedrich Sass claims that the sketches could well be from a two-stroke engine, just like Lenoir's original model.

Whether it was later renamed does not play a major role, because the invention of the four-stroke engine did take place, whether it was in 1862 or later. Sass explains why Otto failed with this engine by referring to the connection between the piston and connecting rod.

In this test model, too, it was by no means rigid. Rather, each piston (not visible here) was supported on a small auxiliary piston, which was intended to absorb the force of the piston on the connecting rod by compressing a small air space.

Otto's idea for the four-stroke engine came from his experiments with the Lenoir engine model. He had experimented with this until he was able to create an ignition of pre-compressed mixture and see its significantly improved effect.

Even without this pre-compression, the engine ran relatively hard, so that Otto feared that it would not survive the constant ignition of the pre-compressed mixture. Sass now suspects that this is why Otto had this buffer installed between the piston and connecting rod in order to be able to better absorb the shocks. And this is exactly where Sass sees the reasons for the failure of this engine.

Because without an exact assignment of the position of the piston to that of the crankshaft, ignition triggering that is only possible from there is not exact. But imprecise ignition can also mean pre-ignition and that's exactly what ruined the engine after it had been running for a while.

If proof is needed, it is certainly in the design of Otto's atmospheric gas engine. The new one had an upright cylinder, later disguised in the style of Greek columns, in which a piston was initially raised slightly, thereby developing enough vacuum to suck in an air mixture. When this was ignited, it shot up and was pushed back down from the atmospheric pressure by the cooling of the combustion gas that took place.

Curiously, however, it did not transfer its torque to a large flywheel mounted on top of the cylinder when moving upwards via a toothed rack, but only on its way down; a freewheel enabled the way upwards without traction.

Anyone familiar with engineering would think that the force should be passed on during the stroke where the combusting mixture creates the pressure. Not so Nicolaus Otto. He designed an engine that avoids precisely this direct pressure transmission.

Once I was with an apprentice class in what was then the Deutz Museum in Cologne and a (very old) museum attendant showed us the engine. Oddly enough, I still (or again) have today the sound in the ear, although not even the of the ignition, but the obvious banging of the piston at the top probably caused the main noise.

If I had known back then that I would one day write a book about the history of automotive technology, I would have gone to Cologne again and interviewed the man. During his presentation, he remarked several times that he still had known Maybach. So, now you can look it up and calculate whether that can be the case.

Unfortunately, the film omits many references to the actual events of the invention of the four-stroke engine. It ends with a tombstone naming Otto as the inventor of the internal combustion engine. That honor goes to Étienne Lenoir, of course. Otto only improved his engine significantly.

In general, Lenoir only appears in the film when his engine is decisively beaten in terms of consumption by Otto's atmospheric gas engine at the world exhibition in Paris. The contemplation which considerations actually brought Otto to the realization of the four-stroke engine is also neglected.