Who would not be interested in seeing the unseen? In seeing the whole new world unfold in something perceived obvious and conspicuous?
From ancient times, humans wanted to see things far smaller than could be perceived with the naked eye. In the XVIth century, such curiosity had led to the construction of a magnifier composed of a single convex lens, which in turn led to the development of the duo scope microscope, as we know it today.
Julia was first introduced to a microscope when she was 4 1/2 years old. We have been using the Duo Scope Microscope, which features three objective lenses: 40x, 100x & 400x magnifications (the eyepiece/ocular lens is 100X). Until the child is comfortable with the concept of focus and magnification, I think it is a good first microscope. It has two light sources:
- to observe a solid item like a shell, use the light source above the stage;
- to observe a transparent item like a prepared slide, use the light source below the stage.
To introduce the correct terminology, we made a Microscope Nomenclature Book. Julia had fun making the booklet, especially weaving a colorful red cord. Why use Montessori Nomenclature? "Children gain a much clearer and deeper understanding of our world when they have the vocabulary to put with movements and images. They say a picture is worth a thousand words, but add a label and now you're talking! From a very young age, children ask what things are called."
At 4 1/2 years old, Julia at first needed help focusing on an object (she would have to move the "stage" to the lowest point, look through the ocular lens and then slowly move the "stage" up until the object is in focus). Patience is crucial in this process as it is very easy to miss the "focus" point while staring at a blur, so she had to get used to the process and know what to expect. But the reward of seeing the mysterious world of magnification was so worth the effort!
The book What's Smaller Than a Pygmy Shrew? is a great introduction to the world of the microscope for a younger child (around 2 years & up). Adrian really loved this book as it explains the concept of relativity in simple terms: things are perceived as big or small only when we have a reference point: the question is What are we comparing it to? For example, a pygmy shrew (the smallest American mammal weighing about 3 gr and about 8 sm long of which the tail takes up 3 sm) can be perceived as small if compared to an elephant, but big if compared to a ladybug, who in turn is huge compared to protozoa, one-celled animals, and so forth.
And what about journaling the observations? Below, Julia at 5 1/2 years old, is recording her observations of a raspberry, an ant-prepared slide, and a sliced blueberry.
While specimens spark great interest in older children, younger ones might gravitate more towards objects that are familiar and/or found in nature. Some of the items we have been observing are sea shells, plant parts, flower petals and leaves (fresh or dry), pine cones, nut shells, shark teeth, coins. Other interesting items might be tree bark, fruit peel, dirt speck, fabrics, salt, sand etc... Also, ask your child - what would s/he want to observe up close ... maybe own hair, fingerprint, nail?
We have collected a few prepared slide-sets, but I would only introduce those slides with which children are already familiar. For example, we have a Set of 25 optic glass prepared slides (including plants, insects, and animal tissues), which comes in a wooden storage case. This set is a little advanced as it is intended for use in biological education, but some slides such as a root of a bean, an onion skin or human blood smear might be of interest even for the little ones.
closing one eye helped Adrian to focus & see the inside of the optic tube
Adrian, at 2 1/2 years old had to get used to looking through the microscope's ocular lens. He could not see anything at first, but there was so much excitement when he was finally able to see the object in focus magnified!
With Adrian, we are only using the 40X and 100X. He is getting accustomed to moving the stage to the lowest point, looking through the ocular lens, and then patiently and slowly moving the stage up until the item is in focus. Prepared slides or two-dimensional images are easier for a young child to focus on.
The World of the Microscope book is very detailed, has a lot of technical explanation and offers many experiments: from looking at an onion skin to one's own hair to making a smear from inside of a cheek to looking at growing crystals found in food. The book is very captivating and will engage your child for a long while. You can also choose a simpler activity at first, and then gradually move to the more complex ones.
Fun Facts about the history of the Microscope:
- The earliest microscopes were known as “flea glasses” because they were used to study small insects.
- The most famous early pioneers in the history of the microscope are Digges of England and Hans and Zcharias Janssen of Holland.
- But it was Anton van Leeuwenhoek who became the first man to make and use a real microscope. He grounded and polished a small glass ball into a lens with a magnification of 270X, and used this lens to make the world's first practical microscope - a powerful lens that could see teeming bacteria in a drop of water. Because it had only one lens, Leeuwenhoek's microscope is now referred to as a single-lens microscope. Its convex glass lens was attached to a metal holder and was focused using screws. The magnification ratio of the single-lens microscope like the one invented by Leeuwenhoek is calculated in the same way as calculations are made for a simple magnifying glass. 250mm--accepted to be the distance of most distinct vision--is divided by the length of the lens.
- The first compound microscope (ones we use today), which incorporates more than one lens so that the image magnified by one lens can be further magnified by another, was created by a father-son duo, Zacharias and Han Jansen in the 1590s.
- Robert Hooke discovered cells by studying the honeycomb structure of a cork under a microscope.
- Marcello Marpighi, known as the father of microscopic anatomy, found taste buds and red blood cells.
- Robert Koch used a compound microscope to discover tubercle and cholera bacilli.
- German engineer Carl Zeiss revolutionized the quality of lenses in the 19th century.
- The smallest object observed through a light microscope was 500 nanometers long.
- In 2008 the TEAM 0.5 debuted. It is the world’s most powerful transmission electron microscope and is capable of producing images half a ten-billionth of a meter.
- Researchers used microscopes in 2013 to demonstrate how life could have started.
For more on microscope use, see here Learning About 🌿Leaves 🔬• Botany 🌸🌳 Lesson.