One of the most important inventions of the Middle Ages is the development of the microscope. With this device, it was possible to examine structures invisible to the eye. It helped shape the principles of cell theory and created prospects for the development of microbiology. Moreover, the first microscope became the driving force behind the creation of new highly sensitive microscopic devices. They also became tools, thanks to which a person could look at the atom.
Historical background on the first microscope
Obviously, the microscope is an unusual instrument. And what is even more surprising is the fact that it was invented back in the Middle Ages. His father is Anthony van Leeuwenhoek. But, without belittling the merits of the scientist, it should be said that the first microscopic device was developed either by Galileo (1609) or by Hans and Zachary Jansen (1590). However, there is very little information about the latest, as well as about the type of their invention.
For this reasonthe development of Hans and Zacharias Jansenov is not taken seriously as the first microscope. And the merits of the device developer belong to Galileo Galilei. His device was a combined setup with a simple eyepiece and two lenses. This microscope is called a compound light microscope. Later Cornelius Drebbel (1620) improved this invention.
Apparently, the development of Galileo would have been the only one if Anthony van Leeuwenhoek had not published a work on microscopy in 1665. In it, he described living organisms that he saw with his simple single-lens microscope. This development is both ingeniously simple and incredibly complex at the same time.
Levenhoek's microscope ahead of its time
Anthony van Leeuwenhoek's microscope is a product consisting of a bronze plate with a lens attached to it and fasteners. The device easily fit on the arm, but hid extreme power: it allowed objects to be magnified by 275-500 times. This was achieved by installing a small plano-convex lens. And interestingly, until 1970, leading physicists could not figure out how Leeuwenhoek created such magnifiers.
Previously it was assumed that the lens for the microscope was polished on the machine. However, this would require remarkable perseverance and extreme jewelry precision. In 1970, a hypothesis was proposed that Leeuwenhoek smelted lenses from glass filament. He heated it, and then polished the area where the glass drop was attached. It's alreadymuch simpler and faster, although it has not been possible to prove this yet: the owners of the remaining Leeuwenhoek microscopes did not give consent to the experiments. However, in this way you can assemble a Leeuwenhoek microscope even at home.
The principle of using the Leeuwenhoek microscope
The structure of the product is extremely simple, which also speaks of the ease of use. In fact, it was extremely difficult to apply it due to the unknown focal length of the lens. Therefore, before consideration, it was necessary to bring the device closer and further away from the studied section for a long time. Moreover, the cut itself was located between a lit candle and a lens, which made it possible to maximize the microstructures. And they became visible to the human eye.
Characteristics of the Leeuwenhoek microscope
According to the results of the experiments, the magnification of Leeuwenhoek's microscope was amazing, at least it increased by 275 times. Many researchers believe that the leading microscope of the Middle Ages created a device that made it possible to magnify 500 times. Science fiction puts the number at 1500, although this is impossible without the use of immersion oils. They simply did not exist then.
Nevertheless, Leeuwenhoek set the tone for the development of many sciences and realized that the eye does not see everything. There is a microcosm invisible to us. And it has a lot more to offer. From the height of centuries, it should be noted that the researcher was prophetically right. And today, the Leeuwenhoek microscope, the photo of which is located below, is considered one of the engines of science.
Some hypotheses aboutmicroscope design
Many scientists today believe that Leeuwenhoek's microscope was not created from scratch. Naturally, the scientist knew some facts about the existence of Galileo's optics. However, with the invention of the Italian, he has no similarities. Other historians believe that Leeuwenhoek took Hans and Zacharias Jansen as the basis for the development. By the way, almost nothing is known about the microscope of the latter either.
Since Hans and his son Zachary worked on the production of glasses, their development was rather similar to the invention of Galileo Galilei. Leeuwenhoek's microscope is a much more powerful device, as it allowed magnification of 275-500 times. The composite light microscopes of Jansen and Galileo did not have such power. Moreover, due to the presence of two lenses, they had twice as many errors. At the same time, it took about 150 years for the compound microscope to catch up with Leeuwenhoek's microscope in image quality and magnification power.
Hypotheses about the origin of Leeuwenhoek's microscope lens
Historical sources allow summing up the work of a scientist. According to the Royal Society of England, Leeuwenhoek collected about 25 microscopes. He also managed to make almost 500 lenses. It is not known why he did not create so many microscopes, apparently, these lenses did not give the proper magnification or were defective. Only 9 Leeuwenhoek microscopes have survived to the present day.
There is an interesting hypothesis that Leeuwenhoek's microscope was created on the basis of natural lenses of volcanicorigin. Many scientists believe that he simply smelted a drop of glass to make them. Others agree that he was able to melt a glass thread and make lenses in this way. But the fact that out of 500 lenses the scientist managed to create only 25 microscopes speaks volumes.
In particular, he indirectly confirms all three hypotheses of the origin of lenses. Apparently, the final answer is unlikely to be obtained without experiments. But to believe that without the availability of high-precision measuring instruments and grinding machines, he managed to create powerful lenses is quite difficult.
Creating a Leeuwenhoek microscope at home
Many people, trying to test some hypotheses about the origin of lenses, have successfully made Leeuwenhoek's microscope at home. To do this, on a simple alcohol burner, you need to melt a thin glass thread until a drop appears on it. It must cool, after which it must be sanded from one side (opposite from the spherical surface).
Grinding allows you to create a plano-convex lens that meets the requirements of microscopy. It will also give an increase of about 200-275 times. After that, you just need to fix it on a solid tripod and examine the objects of interest. However, there is one problem here: the lens itself must be turned with the convex end to the substance under study. The researcher looks at the flat surface of the lens. This is the only way to use a microscope. Leeuwenhoek, the reviews of the Royal Society of which at one time provided him with a glorious reputation, ratherjust how he created and applied his invention.
