The Not So Pure Driven Snow

I had now idea just how dirty snow was, even when it’s not yellow. -K

A few days back I mentioned gather snow in the quest for micrometeorites. I have looked a all manner of things collected from melted snow, regrettably no visitors from space. What I managed to find was primarily biological, various pollen, bits of bark and leaf, and spores of all sorts. A few of the samples had sat around for so long before I got to them that some very interesting fungus had cultured. I found one clear example of Pestalopezia and several unidentified Deuteromycetes and Zygomycetes. The closest thing I found to a micro-meteorite was a bit of soot that I suspect is attributable to the wood stove a the gentleman across the street.

It really was rather surprising the amount of material which I did find. None of the snow I collected appeared as anything other than fluffy white powder when I gathered it, and the detritus which settled out in the melt water was ample to say the least.

Just a Little Reminder

I almost forgot! It is of course a new year and time to renew ones membership in any of the microscopical societies one fancies. I strongly recommend membership in the Royal Microscopical Society. The RMS has a long, and storied history as well as a vibrant and inspirational present. It is an excellent resource for both professionals and amateur enthusiasts. The RMS is welcoming and an incredible resource, whatever ones background and occupation.

Before thinking that a professional society oriented around the microscope and all of its applications and technologies would be a waste of money for a casual enthusiast, one would do well to consider the benefits. There are a number, and they’re all outlined on the RMS website in a better format than I can give here. But I will make my little pitch nonetheless. While looking around their site why not check out some of the past articles in old editions of infocus, the societies popular magazine? I’d say that it alone justifies the price of membership and I look forward to every issue. In the most recent issue there’s a timely article on the basics of capturing photomicrographs of snowflakes, and a really exciting and inspirational look at the latest work of Professor Milton Wainwright who has identified biological entities in samples taken 27 kilometers up in the stratosphere, not the sort of place one expects to find a fragment of diatom!

One other exceptional benefit of membership that I really have to mention is the discount provided to members for purchases at wiley. I recently made use of the discount to pick up the new edition of Current Protocols Select: Imagaing and Microscopy at an excellent price. The 2013 edition has been expanded and updated to the point that I was no longer content to run to the library when I needed to consult it and the RMS discount enabled me to get a copy of my own for a price that didn’t have my long suffering wife locking up my wallet.

Alright, enough of being a shill, but if you’re at all interested in really putting your microscope to use or even just seeing what others are able to do with theirs, consider membership in the RMS or one of the other outstanding microscopical societies.

Happy Christmas, I’m Back Again!

After an extensive and decidedly involuntary hiatus some medical issues have been sorted and I once again have the time and energy for that most excellent pursuit. That’s just one of the fantastic things about microscopic mounting, in many of the processes there are several stages at which production can be halted indefinitely and returned to weeks or even years later without ill effect…

The first step in creating a slide of any sort is not often planning as one might think. As an amateur the first step is more apt to be the acquisition of a specimen; formation of a process for mounting can come later. At present macerated and pressed insect slides are the goal and the methods discussed will be limited to those appropriate. Depending on the particular part of the world where one resides this may not be the most opportune time for the collection of specimens but there is always some supply to be found or purchased. For the sake of simplicity in this first attempt at a mount one may stack the deck in their favor by selecting a hardy subject. I heartily recommend ants.

An ant or ten can often be found in any of the seasons save winter (here in New York anyway) diligently trouping across ones sidewalk or patio. Collection is a simple matter and may be accomplished with whatever container is at hand. Specialized apparatus such as a fine set of forceps or an aspirator can speed up collection but are luxuries rather than necessities. In a popular work concerning ants titled Journey to the Ants, eminent myrmecologists Dr. Bert Hölldobler and Dr. E. O. Wilson spend a page or two on the ease of collecting and preserving specimens in the field be it a South American rain forest or at dinner with Stalin: put the ants into alcohol.

One can use whatever spirit is handy and potent. Concentrations of 80-95% isoproply or denatured alcohol being common and inexpensive make them useful. For our purposes the alcohol acts as killing agent, fixative, and preservative. Live specimens collected directly into a container of alcohol may be stored indefinitely for use as required or removed and desiccated for traditional pin mounting as desired. If one is unable to readily capture ants locally for whatever reason the various retailers who sell ant farms will happily supply a vial of harvester ants for a few dollars delivered.

It’s useful to note that ants aren’t the only subjects which are generally collected directly into strong alcohol. If hunting in the field one happens on an intriguing arachnid Comstock’s classic work The Spider Book recommends collecting into small killing jars or even directly into the strongest alcohol available. The alcohol being decanted and replenished the following day to ensure its potency after the spiders own moistures dilute it.

Spiders and ants make exceptional first specimens as their lack of wings and significant exoskeletons greatly simplifies their processing. That one is generally able to locate several of the same species also helps to ensure that an acceptable slide may be produced. With a significant stock in alcohol on the laboratory shelf one is free to attempt many variations of method to produce the finest results. So do run out and start collecting, or get your ants on order. When I return we’ll begin mounting in earnest, why not come along with me?

Pressed Insects

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The above photo is of three older microscope slides I picked up via eBay for a few dollars. Whole mounts of this sort were once a lucrative business for optical and biological supply houses, and a thriving area of pursuit for hobbyists producing slides of their own. Inarguably, preparations of this sort are very striking under the microscope or even with the naked eye. They are also frequently criticized. Some entomologists, even some microscopists, both today and in the impressive body of historical microscopy and etymology literature, positively railed against slides of this sort. For some, the only proper way to mount insects or arachnids will always be on pin under glass. Why all the hate?; Maceration and pressure.

In order to mount an insect (or anything for that matter) on a slide there are really only two options; incredible thinness or a cell of appropriate thickness, and we wont be dealing with cells today. Some insects (or portions of them) are of a size that may be mounted intact without a cell, however, for the majority that is not the case and the specimen must first be somehow processed. For slides like the above, that processing involves removing all but the chitinous exterior of the specimen, rendering that chitinous skeleton pliable, flattening it so that no cell is needed, and rendering the specimen transparent. Doing so necessarily renders the specimen quite different from its natural state which can lead to false conclusions regarding the species, especially among amateurs.

While the scientific value of slides like the above is debatable, their appeal is undeniable. Some modern slides like the above are available, but they are generally no where near as plentiful, or as well prepared as they were fifty or more years ago. So, is the present day microscopical hobbyist limited to the dozen or so species that may be found from the modern suppliers or what may be scrounged up second hand? Of course not! With a few rather common supplies and a bit of patience one can produce pressure mounted insect slides of their own. After all, I’ve done it with perfectly passable results; and believe me, if I can do it, so can you.

In the next few posts I’ll be going through the process from collection to completion and pointing the way to some classic works that provide much more exacting procedure than I. 

Times, Diameters, and Public Domain Books!

A big part of what I do with the microscope comes directly out of books. I have no formal training with the microscope so books dealing with it usually contain something that I was totally unaware of, or just provide a solid footing. Occasionally they clear up misconceptions, which happed just this morning actually.

Microscope objectives are designated in many ways, but chief among them is by their magnification. Unfortunately for the beginner, there is more than one way to describe the magnification of an objective. For quite a long time objectives (and oculars) were described and marketed primarily by their focal length. They might also be described by the times they magnify an image, (as in 10x, 40x, 100x) or by the diameters of magnification they provide; a way that until recently I thought synonymous with the times designation.

The focal length of an objective (if you’ll forgive a generalization) is really just the distance from an object at which the objective is in primary focus. There are a few factors that can alter the distance for practical reasons, but in essence an objective with a focal length of 4mm needs to be 4mm from the object it is focused upon, an 8mm at 8mm, a 1/12in at one twelfth of an inch and so on.

An objective might also be described by the number of times it magnifies an image, the today ubiquitous “X” marked on nearly anything with a lens. The square root of the number of times magnified, provides the number of diameters of magnification. So that it may be said an objective that magnifies twenty five times, provides five diameters of magnification. Who knew?

I can say that I have seen articles and forums where the term “diameters” is used when speaking of “times,” I’ve even done it myself. Let us now turn to an old authority, Alfred Cheatham Stokes, in his book Microscopical Praxis:

A lens of any kind magnifying ten diameters is said to magnify one hundred times, or ten diameters in each direction, “times” representing the square of the “diameters,” and the diameters the square-root of the times.

It’s certainly odd that this does not appear to be more widely known, or Stokes more widely read. Microscopical Praxis is out of print and has been for years, so long in fact that it is in the public domain and one can find it nearly anywhere that handles or reprints public domain books.  Here’s a link to it at the Internet Archive.

Very Basic Chemistry

In preparation for an upcoming effort I will need to mix up a solution. This solution needs to be of a particular concentration and to do that I’ll need to think back to chemistry class. One of the best parts of chemistry was mixing things together just to see what would happen, whatever the results. However, when one wishes to create something specific it’s important to know how to go about it.

It’s been my experience as an amateur microscopist that there are generally two types of guides out there; those made for children, and those made for professionals. I’m not saying there are no guides for the enthusiastic amateur, there are many very nice websites, periodicals, clubs, societies and forums out there which provide both advanced and accessible resources, I’m simply pointing out that if one picks up a book on the microscope or microscopic methods it’s apt to be either highly technical or exceedingly simplistic. Even the most technical of microscopy books can be wealths of information for the amateur, but such works often make certain assumptions concerning the knowledge of the reader in other fields, particularly chemistry.

Suppose one day in an effort to properly treat a specimen one follows a guide that calls for a 10% solution of something. At this point one has two options; purchase the solution, or purchase its components and prepare it ones self. If each of the components of the solution are liquids it’s a simple math problem. Computing the necessary ratio of components for any desired final volume is the work of a moment. However, when mixing a dry component and a liquid component things might get a bit tricky for people who have forgotten about mass.

To determine the ratio of two ingredients necessary when one is a solid and the other a liquid one must first measure them in a common unit, mass. When measuring each ingredient by grams it makes no difference if one or both is liquid or solid. To make things even simpler, one can look up the mass of a given volume of nearly any liquid and measure out the liquid component in milliliter and the solid component in grams.

The next time you see a recipe that calls for one part this and four parts that, just remember that the unit in which you measure is inconsequential so long as all ingredient are measured in the same unit, and consider buying a balance.

John Jacob Bausch’s Estate

People who know microscopes know a company called Bausch & Lomb. People from Rochester, New York might know the know a bit more, because that’s where the two German men founded their company. They started small, and became quite rich. In any case, sometime after making it big, John Jacob Bausch built a great big house on the shores of Lake Ontario. That mansion is currently for sale. See the realestate listing here, or read a little article from the local newspaper here.

It begins.

I, have a great affection for the microscope; it’s a fantastic tool that can reveal the world in a way the eye alone can not. With a microscope one can look at things differently, deliberately. One hesitates to mention seeing “the ocean in a drop of water” the phrase having been so often repeated, it looses not only it’s meaning but it’s power to entice interest. There is more in the world than oceans and more in the dust on ones mantel than lax housekeeping.

The microscope was once a magnificent invention, a wonder, able to command the attention of the finest minds and richest kings. Those first instruments were crude optically, difficult to operate, and secret. Antonie Philips van Leeuwenhoek saw the hidden treasures of the world around him and shared it with all who would listen, but never revealed the secrets of his microscopes construction. Not until the 1950’s were the finer points of his methods found out. Long after the toys on department store shelves surpassed his finest efforts in both magnification and resolution, van Leeuwenhoek garnered attention. What van Leeuwenhoek did beyond grinding lenses and peering at wonders, was get people interested in what he was doing.

Today anyone can buy a microscope. From a toy with plastic lenses to a scanning electron set up, microscopes are available to everyone and can be found to fit every budget. They are ubiquitous to an extent that most people know  at some level how to operate them, even if they don’t know the finer points. Few students will complete their education without at least examining a bit of onion or a smear of cheek cells on a microscope slide. For many people their exposure to microscopes ends there.

It doesn’t have to end though. Microscopy can be pursued for little expense and prove to be a rewarding hobby. Unfortunately, it can be quite daunting to make the leap from looking at a drop of water to staining a cut section, or building a collection of permanent mounts. While there is an abundance of information available for the beginner, and countless specialized texts for professionals, there is not a great deal in between for those who are not students.

I propose to make some meager effort in this regard and document some of my microscopic pursuits here. Perhaps it should prove useful to someone.