Samuel Serpent
Picture by Brett_Hondow CC0 via pixabay
When I think about my early childhood, there is one picture that comes up from time to time: It’s my grandfather standing before the so called “weather station”, a wooden panel with three brass gauges: a thermometer, a hygrometer and a barometer. Then my grandfather gently knocked against the glass lid of the barometer with his knuckle and checked the barometer again. As a child I was convinced he woke up the little worker inside, who in return checked if the weather would become fair, rainy or if it was changing. This made perfect sense to me, because I knew there was a special force responsible for the weather: the weather fire dwarfs. After the evening news the news anchor would say “And now the weather fire dwarfs for tomorrow”. It was much later that I asked my mom and she explained to me that it wasn’t the “Wetterfeuerzwerge” (weather fire dwarfs), but the “Wettervorhersage” (weather forecast). Until then, I was convinced that being a weather fire dwarf was just a job like being a firefighter, a baker or a teacher. They looked out for the weather and made assumptions on how it was going to be. It also made perfect sense that this job was done by dwarfs, given the small instruments they needed to operate in.
You might wonder where I’m heading to with those seemingly random childhood memories? Now, my grandfather certainly did neither wake up the little weather fire dwarf, nor did he perform some other kind of magic. He just made sure the barometer, which had a small metal box called an aneroid for measuring the pressure inside, was showing the tendency. When you tap them, the pointer will move to the current pressure, giving you an indication if the air pressure is rising or falling. He also knew that the little markers that read “very stormy”, “rain”, “change”, “fair” and “very dry” were not to be take literally. In winter “fair” weather often meant it became very cold. He not only looked at the barometer – he also knew how to interpret what he saw.
Fast forward to 2018 I struggle with explaining the use and the accuracy of sensors to colleagues. I can’t fight the feeling that digital has somehow taken a toll on our imagination and our expectations towards instruments. It’s especially true for hygrometers, as humidity is far more complicated to measure exactly than temperature 1. A digital hygrometer usually provides you with two digits behind the comma. So instead of reading a little above 50% on the analog hygrometer it provides you with a straight 51.23 % relative humidity. That’s astounding. Sadly, it doesn’t mean what people think it means. Because it seems to provide such an exact figure, people assume it’s more accurate than the analog reading of grandpa’s old weather station. But it isn’t necessarily so. If it’s a very good digital humidity sensor with a 1.5% accuracy the reading will mean it’s somewhat 50 to 52ish. If it is a more common sensor with a given 5% accuracy it tells you that it can be anything along the lines of 46 to 56% 2
Picture by Alexas_Fotos via pixabay CC0
But why are they giving two digits behind the comma anyway, is this just a fancy feature? Yes and no. For that, we have to understand the difference between accuracy and resolution, both specifications you will find when you are buying a datalogger or sensor. What we just talked about is the accuracy. The resolution is often higher than the accuracy. Your humidity sensor might have an accuracy of +/- 2% RH, but a resolution of 0.1. This seems like a contradiction at first, but it isn’t. Let us imagine a little weather fire dwarf who is able to feel how wet it is. He says: “It’s 52%”. Now, while we saw that this can mean anything between 50% and 54%, if we send him out again, he will be able to tell us if it is becoming wetter or dryer than before. And he will be able to tell us more detailed than he can do it with the general humidity. He is able to say: “It’s getting damper, now it’s 52.1%.” So, while the digits behind the comma mean nothing in terms of general humidity, they can help us understand where the climate of a room is heading to and how severe the changes are. If you measure every 5 minutes and get a reading of 52.1%, 52.3%, 52.2%, 52.1%, 52.2% and 52.1% over half an hour it will tell you something else than a series that reads 52.0%, 52.2%, 52.3%, 52.4%, 52.6%, 52.8%. While both series can still mean it’s 2% more or less humid, the tendency of the second series shows that something is going on which makes the room damper. Think of the resolution as a measurement that helps you to see change, just like grandpa tapping on that old barometer.
Next up, we will ask the question if sensors really read the temperature and humidity of a room.
Here comes the 2nd part…
Angela
Kärcher WD 5.600 MP
As the name suggest, they are usually outfitted to do both: to vacuum water AND dry stuff. But here’s the thing: they can only do one of those things at once. Therefore, it’s usually preferable to assign one vacuum cleaner for wet-only use. If you can’t afford two vacuum cleaners, I’d suggest making sure this one is always emptied at the end of the working day, so you don’t accidentally end up with a tank full of muddy dust, grime and sawdust that is nearly impossible to empty.
Now, what should you consider when buying a wet-dry vacuum cleaner? They come in a wide range of prices and functionalities, so it is like always a big “depends”. But here are some thoughts:
Capacity is often a big factor for the price, so you should ask yourself which scenario is most likely to happen. The occasional leaking roof is a big risk for the artifacts but usually just leaves small water puddles. So, a small tank with a capacity of only 10 to 20 liters will probably be enough, even if it means you have to go a few times and empty it. If your usual suspect is an insufficient drain system that leads to water coming back from the sinks and the toilets (yuck!) as soon as there is slightly more rain than usual, you probably need a larger tank. If this happens on a regular basis or large amounts of water are involved, you might want to look for a sump pump and the installation of a backflow trap.
Nilfisk Alto Aero 25
Speaking of wheels: if you do have to move your vacuum cleaner over larger distances and uneven ground how good the wheels are and how easy it is to move around can also be a determining factor in your buying decision.
One thing closely related to handling is the response time. As I said at the beginning it’s always best to have your vacuum cleaner for wet-only use. But if you can’t have one what it takes to convert your dry into a wet vacuum cleaner can determine your decision. For example: With my blue one, I have to remove the filter bag and the filter cartridge and put a special textile bag which serves as a fine filter over the motor before I can vacuum water. If I miss that step, I will destroy the vacuum cleaner. With the yellow one I’m good to go as soon as I have removed the filter bag. I do have to remember, however, that in this case I’m NOT allowed to remove the filter cartridge as it is necessary to protect the motor and if I do it like I would do with my vacuum cleaner at home I would inevitably destroy the device.
Closely related is the question if the vacuum cleaner can be operated in all corners of your storage or museum. So, how long the power cord is can be a factor in your decision. But even if your vacuum cleaner does have a rather long power cord, chances are that it is still not sufficient for that special far away corner of your storage. You may want to test out the action radius of your vacuum cleaner BEFORE the first incident and want to store it together with a cable drum of sufficient length.
Another important question is maintenance. This involves how easy it is to clean and to repair. You sometimes see no-name vacuum cleaners at a bargain price, but you should take a close look at the parts that are most likely to get lost or broken. The nozzles, for example, should be a standard size you get in every DIY store, not some exotic caliber that is a standard in the North-Western Black Forest. Same with the bags, filters and screws. All parts should be easy to disassemble and clean because you will inevitably suck some strange thing in that will get stuck half way in the hose. In that case it should be easy to remove the hose and clean it.
Some “Gotcha!” things are not so obvious: For example, I talked about leaving the filter cartridge in place with our yellow one. Now, here’s the thing: Of course, the cartridge, which is made of some sturdy paper plastics mixture, gets wet when I vacuum water. In order to dry it, I have to remove it after use. One thing is that I have to remember to put it back or the next one who uses the vacuum cleaner will destroy it. And the other is that I’m not completely comfortable having a soaking wet paper thingy around my storage because I always fear mold. I probably consider how this problem is solved in future purchases.
Your own vacuum cleaner will probably need some special skills we haven’t considered so far. Maybe you do have a lot of water in your storage occasionally but also sometimes only small puddles. In this case you might want to look for a vacuum cleaner which can also be operated as a pump by adding an additional hose for transporting the water directly to a drain. Or you have water in hard to reach places, so you might want to look for a model that has a telescopic suction tube or multiple attachable suction tubes to reach there. Sometimes being able to turn the device to blow instead of suck can come in handy (our yellow one has that functionality). Whatever it is, make sure your superhero has all the superpowers it needs!
It’s a favorite tool I wish you all will never need to use in an emergency!
After our poll you might have asked yourself what we did with the whiskey wagons in the end?
Emptied Whiskey Bottle
Well, we emptied the one that was already open as we considered the whiskey could probably evaporate over time and damage the wagon. The plug already looked a wee bit suspicious. We left the sealed bottle untouched. We didn’t accession the whiskey as we assumed that if the whiskey itself will become a subject of research, scientists could still examine the whiskey in the sealed bottle. Of course, we documented all of this in our database.
Full disclosure: Our expert on all things whiskey said it will not get better or gain more value if stored in a bottle, but he also assured us that it should still be good. Strangely enough, none of us was willing to volunteer tasting it.
I’m all excited that I was chosen to speak at the European Registrars Conference in London, taking place November 17-19 (see full program here: http://www.erc2018.org/programme/programme/ ). I will represent the TECHNOSEUM (www.technoseum.de) and speak on “Collections management by the truckload” or how to get a grip on large collections. Time to share with you all the ups and downs of managing the thousands of objects that hit my colleagues and me when we accepted a large collection of advertising materials, a collection from a former radio museum and a collection of broadcasting equipment from our state’s broadcasting company. It will also be a great opportunity to meet old and new friends.
Hope to meet some of you in person there!
Angela
It’s been a hot summer in many regards. Temperatures were ridiculously high in Germany and while some places saw exceptional drought and wildfire, others saw heavy rain and thunderstorms. It’s nearly a metaphor for my working life. There were the usual ups and downs in collections management, aggravated by the problematic weather conditions. Then, there is one of my side jobs which has to do with work related legal issues and solving conflicts. This one required more of my time and ability to write than usual. Long story short, I remembered to practice what I preach: that good collections care always means taking good care of yourself in the first place.
Registrar Trek was one of the things that I put on hold. I stayed away from this highly work-related blog and social media activities in general and instead focused on improving my soldering skills (which are still my main obstacle in all things microcontroller), dabbling with the 3D-printer and taking baby steps into woodworking (if you are interested in learning how to fix things and become more comfortable with tools in general, definitely look at Leah Bolden’s excellent “How to” videos at See Jane Drill).
With the fall approaching things start to look a little less turbulent and I hope I will be able to fill the blog again with interesting things. Of course, all is easier if you help with it, so keep pictures, stories and articles coming to story@museumsprojekte.de
Best wishes
Angela
Recently, we received this railway waggon. It’s from the Jim Beam Wheel Series, Beam Trains, Caboose – Red #91197
As you probably already guessed, this waggon isn’t “innocent”. It contains a porcelain whiskey bottle (with whiskey 150 months old when bottled).
And of course, part of the whiskey is still inside.
And there’s another one from the same series which also contains whiskey – and in this case the tax seal of the bottle is still intact.
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Growing up in the middle of Europe my earliest Easter memories are joyfully searching for Easter Eggs in the garden. Many years later a recurring task in my professional life is searching for things that are not where the database says they should be. For this Easter I thought I’d write about the differences:
Searching for objects is not joyful
While as a child the search for the Easter Eggs is full of joy, the search for an object is all but that. You search for an object because it is needed, often needed fast, for a research request, loan or exhibition. There is time pressure and if you don’t find it, it has consequences. It can mean a whole lot of work for other people, like curators having to search for alternative objects that convey the same message as the original object. It can mean that whole parts of an exhibition must be changed because they were designed around this special object. It can also mean that a researcher can’t answer the question s/he is working on.
Objects are not hidden on purpose
Other than Easter Eggs no one hides objects on purpose. While a small portion is really stolen, most are lost because people miss to record or communicate location changes (we already looked at this in Failures in Figures). The reasons are multifold: thoughtlessness, laziness, arrogance (“That’s not my job”), confidence in the own abilities to remember everything, the belief that “I just take it out now and put it back in immediately”. No traits of the Easter Bunny but of many museum professionals.
Recently I discovered an additional reason why object locations are not updated: magical thinking. The belief just because there is Wi-Fi in the storage and the objects are barcoded a magical superpower knows exactly where each object is. Sorry folks, that’s not how it works.
Looking in all the right places
While searching for Easter Eggs is often unsystematic or just starting at point X and ending at point Y of the garden, searching for objects requires a different approach. If your storage has 3,000 square meters and much more shelf space, you can’t just search everything. And you can’t just go into the storage looking for the object. Instead, the first thing you do is a hands-off approach. You think about what most likely happened to the object.
“I’m quite sure there was one more, was there?”
A mindful use of energy
As a child on Easter morning it’s great to run into the garden full of energy and search for those eggs. As a museum professional with a tight schedule and a lot of tasks on your plate you have to be more mindful about how you will approach the search. You have to weigh the time you can invest in the search against the likeliness of finding the object.
If the object can be retrieved with just a few phone calls, everything is fine. If the object is needed next week and the last storage location is a place that doesn’t exist anymore (i.e. because you disassembled the shelves or moved into another storage location 10 years ago) it’s probably better to inform the researcher or curator immediately and ask her or him to look for an alternative, if possible. If there is a high likeliness of the object being in a pile of boxes that don’t have proper location entries, it’s probably best to work through this pile updating all locations – you will save yourself a lot of time for future requests.
Make sure you know that you don’t know
Remember as a child searching the same place twice because you forgot whether you have looked under that tree? You should make sure this doesn’t happen to you when you search for an object. The most important thing is to mark an object as “location unknown” as soon as you discover it isn’t where it is supposed to be. That way everyone knows the object is not accessible at the moment and can already think about alternatives. It also helps you to keep an eye on all the objects with “location unknown”: Is their number in the database decreasing, chances are you are doing a good job as collections manager. If the number increases, chances are there are problems in your collections management and logistic workflow and you might want to take a closer look to find the underlying issues.
That you should tick off the things you already did to find the object on your list should go without saying.
I hope the only thing you have to search for now are real Easter Eggs.
Happy Easter, all!
Angela
What makes your collection special?
First you need to decide if you make a documentation of your whole museum or if you split it into different collections. That depends how large your museum is and if different people are responsible for different collections.
Overview of the collection
On your way to the storage there are a few polite questions. Now you have a bit more time to answer, but stay focussed: Give an overview, do not go into details of collection concepts or the donor’s biography. That will come later.
Maria Scherrers
Maria Scherrers is museum specialist with degrees from HTW Berlin and the University of Leicester. She spent most of her working life so far in company museums and collections. She is fascinated by the way our everyday life is changed by brands and how that influences our cultural history and what we will be collecting in the future. In the mean time she is a consultant for company that wish to build and use historic product collections.
She spends her little free time on her family and on politics.
www.historicalassetmanagement.de
Documenting what you did and why will help your future self.
Just imagine 20/50/80 years ago one of your predecessors had documented what they did, why they did it and how they did it. Wouldn’t it be wonderful to understand where this object numbering system comes from, who meticulously documented that part of the collection on index cards or where that part of the collection was stored over the years.
Over the next weeks I want to post some questions you might want to answer for yourself. Think of what all the people coming after you might want to know about your collection work.
These topics will be part of the questionnaire:
1. Overview
2. History of the Collection
3. Collecting and Collection Criteria
4. Documentation and Documentation Criteria
5. Digitisation and Object Photography
6. How the Collection is used
7. Storage and Conservation
8. Plans and Future Developments
Stay tuned!
Maria Scherrers
Maria Scherrers is museum specialist with degrees from HTW Berlin and the University of Leicester. She spent most of her working life so far in company museums and collections. She is fascinated by the way our everyday life is changed by brands and how that influences our cultural history and what we will be collecting in the future. In the mean time she is a consultant for company that wish to build and use historic product collections.
She spends her little free time on her family and on politics.
www.historicalassetmanagement.de
