Calibrator Exciter; Model: C31
Geophysics; Soil Science; Geo-Mechanics
<strong>Physical Description</strong><br /><br />The two Calibration Exciters are mounted to a sturdy cement wall by 4 steel screws at each corner of the base. The base is comprised of a non-magnetic metal alloy that has a square plate flush against the wall and two perpendicular plates which the driver coil sits between. The field coil casing is made from the same non-magnetic material and contains loops of copper coil which are partially exposed on the front side by 4 holes in the casing. The field coil is connected to the driver coil by a magnesium rod. The two coils are held in place by a large, non-magnetic, metal alloy, vertical clamp that that is positioned against the front side of the driver coil and the rear side of the field coil. The field coil has a receptacle with four pin holes: two for AC current, and 2 for DC current. The driver coil is connected to a steel connector, which must be at least 3” long which then connects to the desired test equipment or vibration table. The current is measured in the coils by a connected ammeter. <br /><br /><strong>Functional Description</strong> <br /><br />The main use of the Calibration Excitor is to calibrate vibration pickups, and displacement of acceleration by directly attaching to the vibration table and applying a frequency. The field coil is supplied a DC voltage which creates a steady magnetic field around it. The driver coil is within the magnetic field, and the driver coil is supplied an AC current with adjustable frequency and amplitude. The frequency created by the driver coil is used for calibration and to generate force to be applied to the vibration table and testing equipment and used to find the resonant frequency of the tested
1946
physical object
English
UNITED STATES PROPERTY | U.S. 2322 | UNIVERSITY OF FLORIDA
PROPERTY OF | UNIVERSITY OF MICHIGAN | 541815
USA
Washington Densometer
Soil Science
<p><strong>Physical Description<br /></strong><br /><em>Main apparatus</em>: <span> </span>The Washington densometer is comprised of 16 pieces (The kit owned by MTU does not include all 16 pieces). The first of these pieces are 4 aluminum calibrated rods, which have a large hexagonal head on them, screw threads at the base, and an inscription reading from 4 to 16 at each inch mark. Then there are two four-inch long aluminum bleeder plugs with an inscription from 0-4 at each inch mark and screw threads at the top and bottom. There is then the aluminum cylinder cap that has a hole in the exact middle which the bleeder plugs are able to penetrate, along with a small pressure release valve. A piston comprised of aluminum and rubber gaskets sits underneath the cylinder cap and is fitted with screw threads at the top to join to an adapter. The piston sits in the main body of the apparatus. The main body of the apparatus is a hollow aluminum cylinder that sits upon a main valve made of brass, complete with a blue painted knob. This main valve is then attached to an aluminum cast coupler. This coupler allows the main valve to attach to a conical cast aluminum base with a fitting at the top that fits the coupler, also called the Head. On either side of this base, two “wings” are present that allows the conical portion to be attached to another base.</p>
<p>Two ground bases are available for the apparatus. One is called the carrying base which is a green painted wood and aluminum base that is a square, flat, piece of wood upon which a short hollow cylinder is placed. On either side of the cylinder are two brass screws with two wing nuts that fit into the wings on the Head and allows the bases to join. The second possible base is a circular piece of wood with a circle cutout in the center, also called the Template. The circular cutout has an aluminum fitting around the edge in which one of three different height hollow columns can be placed. Two brass screws with wings nuts are also present on the wooden base so that the conical base can be attached. Three aluminum rings are also present, whose exact volume is known. These rings are used for calibration of the tool. A flexible suction tube is also part of the kit. This tube is made of a spring that resides inside of a silt screen. A tapered aluminum sleeve, with interior screw threading is also present. <span> </span>The kit also includes 2 quarts of D-87 soluble oil, and 1 pint of D-87 soluble oil. An extra rubber gasket was also included in the kit, though the reason for it is unknown.</p>
<p>According to photos found in the “Suggested Method of Test For Density of Soil in Place Using the Washington Densometer”, it looks like the kit that is housed at Michigan Technological University is missing parts. Parts that are not included in the kit are a recharging valve, a balloon, and a locking ring.</p>
<p>The apparatus is housed within a large wooden box with steel handles on the sides for transportation.</p>
<p><strong>Functional Description<br /><br /></strong>To use the apparatus, the user would first assemble the apparatus with the template base. The Densometer would then need to be calibrated appropriately. In the use of the Densometer an initial reading, a final reading, and a ring constant would be recorded. With these reading a volume would be produced. The soil removed from the test hole would be measured for weight. With these two measurements, the density of the soil can be determined.</p>
1960s or 1970s
English
physical object
USDA property tag 061040-00900
USA
Picket Model 1000 Slide Rule
Mathematics
<span style="text-decoration:underline;"><br /><span>Physical Description:</span></span> The Pickett 1000 slide rule is made of three rectangular bars of aluminum alloy coated in plastic with grooved slides. Two bars are connected at the end with braces that are mounted to the flat side of the bars and the third bar is free to slide between them, held in place by slide tension springs. The two outer bars are called stators and the inner bar is referred to as the slide. The slide rule also has a courser made of two flat lenses held together by aluminum above and below the upper and lower stators. Each bar of the Pickett 1000 slide rule has at least one scale on it. The front side of the slide rule has the DF scale on the upper stator CF, CIF, CI and C scales on the slide and D and L scales on the lower stator. The back side of the slide rule has an A scale in the top stator B, T, ST, and S scales on the slide and K and D scales on the lower stator.<br /><span style="text-decoration:underline;"><br />Functional Description:</span> <span>Slide rules work on a system of logarithms. In order to do multiplication the slide rule adds two logarithms and takes the antilog to determine the answer. Because the slide rule uses logarithmic scales, the operation is simplified. If the user wanted to multiply two numbers together they would move one of the indices on the C scale to the first number that they wish to multiply on the D scale .They would then move the cursor to the second number in the multiplication on the C scale and look at the corresponding number on the D scale. So, if you wanted to multiply 2 and 4 you would move the left index of the C scale to the 2 on the D scale, move the cursor to the 4 on the C scale and see that the answer Is 8. To do division the inverse is done. To find the square and square root the A or B scale and the D scale are used. Locate the number of the square root you want to find using the cursor, when found the corresponding number on the D scale is the answer. To find the square the inverse is found. cube and cube root K scale and the D scale are used. To find the cube root take the number and find it on the K scale read the corresponding number on the D scale. To find the cube the inverse is performed. Scales available on the slide C and D used for multiplication and Division, CF and DF used for multiplication and division when the C and D scales run out. The CI and CIF scales are the inverse of the C scale and CF scale respectively. The S T slides are used for sine and tangent of greater than 5.7 degrees while the ST slide is used for degrees less than 5.7 degrees. The A and B scales are used in the calculation of squares and square roots. The L scale is used for the Log base 10 of a number.</span>.<br /><span><span><br /></span></span>
Trevor Cretney, Adam Kausch, Matthew Luebke, and Adam Miller
International Slide Rule Museum. ISRM is the world's largest free digital repository of all things concerning slide rules and other math artifacts. There are over 7000 Images or PDF's in the ISRM Galleries">. Web. 22 Mar. 2017. <http://sliderulemuseum.com/SR_Scales.htm>.
Konshak, Mike. Pickett Chronology. JPG.
Hartung, Maurice L. How to use the Ortho-phase duplex slide rule. Pickett & Eckel, 1948. PDF.
1957
English
physical object
United States
Wheatstone Bridge
electricity, physics
<strong>Physical Description</strong><br />A circular brass cylinder on a thin steel plate mounted on a wooden board, screwed into a base wooden plate at three spots: the top and bottom two corners. Two brass knobs at the bottom front of the wooden plate can be loosened and tightened. These knobs have ribbed edges and are binding post terminals. It would appear that wires come out of the bottom of the cylinder through the wooden board and attached to the binding posts from the bottom. A lever at the left top of the brass cylinder rotates to start and stop. A small square pin sticks slightly out of a small hole in the middle bottom of the base. The wooden plate also has small holes in each corner.<br /><br /><strong>Funcitonal Description</strong><br />It would appear that one winds up a spring inside using the square shaft/socket on the front like winding a clock (We did not attempt to work the machine, as it no longer has its key). The switch at the left then allows the spring to turn a rotor inside that spins inside a set of permanent magnets, which would create alternating current. Presumably, then, the Wheatstone bridge rectifier turns the AC into DC and the DC current could be tapped from the two binding post terminals on the front. But the fact that the diagram on top of the case shows resistors rather than diodes makes this interpretation less ceratin.
Timothy Maze, Liam Anderson, Zach Nicholas, Peter Amundsen; expanded by Steven A. Walton
c.1890s-1910
English
physical object
C 108957.
Property tags(? not MTU): 2900 and 12501, the latter on the plastic pressure tape (Dymo was one brand) that was popular from the 1970s-1980s
United Kingdom
DC Voltmeter, Model 1, NO. 5541
Physics
Electricity
<strong>Physical Description</strong><br />A Wooden/Brass Instrument that is housed in a Wooden box with a lock on the top and a leather handle on the side attached by two metal fasteners. The tool itself has a dial separated into increments of 10. It has 3 black plastic knobs that can be unscrewed and a button/switch on the front face. It also has multiple model numbers and a calibration screw on the bottom<br /><br /><strong>Functional Description</strong><br />Measures the DC Voltage between 2 inputs, an optional 3rd input can be used as well. The DC Voltage Potential between the inputs is displayed by the dial on the front of the instrument. The instrument itself is rated for 150V maximum and 3V minimum. The box for the instrument serves as a carrying case as well as a protective shield to the outside environment.
Timothy Maze, Liam Anderson, Zach Nicholas, Peter Amundsen with additions by Steven A. Walton
late 1890s or early 1900s; July 12, 1930
physical object
Enlglish
painted inventory no. on front: J161a
Model 1, NO. 5541; 40677, 2900, MCMT-8896
USA
Surveying Transit
Surveying
Physical Description:<br /><br />The transit is broken up into three different layers. Starting at the base, there is a opening in the bottom allowing the device to be fixed to a tripod, or legs as they were referred to by Gurley, the creator of the transit. (1) Just above the base sit three brass leveling screws which supported the brass leveling base. On top of the leveling base were the lower horizontal tangent and locking knob. A small, cylindrical support leads from the leveling base to the circular Vernier Plate. In the middle of the Vernier Plate is the compass, which has a steel interior and a brass exterior. The compass is held in place by two needles. On the outside of the Vernier Plate as N and W, there are two Plate Vials, or levels. At W and E of the compass, there are twin supports that lead up to the telescope. At the top of one of these two-legged supports is a vertical circle which runs parallel to another Vernier Plate to find relative angles. Suspended from the two-legged supports is the telescope. Below the telescope is another level. <br /><br />Functional Description:<br /><br />This device is used to measure very precise angles both vertically and horizontally. The surveyor would set the device on a flat surface and look through the transit to sight it in on point they wanted to know relative to them. They would then take the compass and vertical dial angle readings. This process takes a bit of patience. First, they adjust the four base knobs until the device reads level on the two levels next to the compass, assuring accurate measurements. Failing to do so would cause the surveyor to grossly miscalculate their position. They then line up the compass so the north lines up with the needle. At this point, the surveyor unlocks the transit scope from it horizontal and vertical axes and point it at the point in question. The surveyor uses the focus knob on the side of the scope to get a clear image then locks the scope in place. The surveyor makes further horizontal and vertical adjustments using the fine adjustment knobs and checking the progress through the scope. When satisfied that the scope is on point, the surveyor takes the horizontal bearing from the gauge around the compass and the vertical angle from the vertical dial on the side of the scope. These measurements can be used to help calculate distances and elevations using trigonometry.<br /><br />1. (Gurley Manual of Surveying Instruments)
Timothy Judge, Xena Cortez, James Dykstra, and Conner Deur
Between 1880 and 1908
English
Physical Object
No accession number
United States of America
Chainomatic Analytical Scale
Apothecary;Jeweler: Chemist
<h5><strong>Physical Description</strong></h5>
The scale’s frame is a rectangular prism composed of a russet-colored wood, with some sun bleaching occurring to its front face. Three tarnished metal feet, one on each front corner and one placed in the middle of the rear side, hold the frame about 2 cm above the ground. There are four glass-paneled doors that allow access to the actual measurement apparatus. A 145 mm x 235 mmm door on the top side that can be removed fully from the frame, and has a handle on the left and right sides that can hold it securely in place. Two 162 mm x 150 mm hinged doors are set into the left and right side of the frame, with securing handles being placed on the side of the door the corresponds to the frame’s front side. The fourth door is the primary access way to the scale; it is a vertically sliding door, 289 mm x 230 mm, with a worn white knob of an unknown material at the base that can be used to lift it up. The door can be lifted completely out of its slots, but two strings prevent it from being detached from the frame completely. The rear side is made up almost entirely of a pane of glass. <br /><br /> Two letter and number combinations are printed on the frame: MCMT-9614 appears on the bottom left of the frame’s left side; R20770 on the bottom left of the frame’s right side. They may be the scale’s make and model numbers, or possibly relate to the production and manufacturing process of the scale.<br /><br /> The scale apparatus itself rests on a polished black layer, made of either ceramic or stone, that is positioned 40 mm above the bottom of the frame and extends past the four wooden sides. Two metallic gray weighing platforms hang about 20 mm above the ceramic base, suspended from hooks about 220 mm above the base. A metal hanger for suspending weight is welded between the <a title="Image of Original Wrappings for the Chain" href="https://www2.humboldt.edu/scimus/HSC.36-53/Images/CB_AB2_ChBox_contents.jpg" target="_blank">two small metal rods</a> that hold the platforms to their suspension hook, though the hanger for the left platform has broken off, and a metal peg has been secured to each of that platform’s rods to hold the hanger up. The stirrups for the the platform suspension hooks rest below a “100 mm” measurement poise that tops the scale apparatus; this measured displacement can then be used to determine the weight of the objects being measured, in grams. Descending from the measurement poise, the scale’s pointer ends at a small cream-colored piece of plastic, 6-sided—though similar in shape to a hypotenuse. The plastic piece has the words “Christian Beckering Inc., New York” printed across the bottom, while the scale’s measurement lines are printed almost microscopically along the top. The scale’s central pillar, support beams, and base are all formed out of brass. A solid brass cylinder also extends out from the base toward the front of the frame. An adjustable-angle magnifying glass that is used to make out the measurement lines can be slid on and secured to this cylinder if the scale is undergoing frequent use, though the lens has been removed from this particular scale’s magnifying glass. <br /><br /> Two apparatus control knobs are located on the wooden frame: one on the front side, directly below the front door’s lifting knob; and one on the right side, at the middle along the top. The front knob can be rotated clockwise and counterclockwise to adjust the sensitivity of the measurement platforms. The right knob can be rotated in either direction, and pushed in and pulled out, though not entirely. The particular purpose of this knob is unknown because its mechanisms in conjunction with the rest of the scale are broken, though it may have once served to adjust the balance of the scale. <br /><h5><strong>Functional Description</strong> </h5>
In order to use the scale, the user must adjust the knob on the front of the wood box that will move the stoppers under the metal plates. This will keep the scale from moving when adding the object/weights to each of the metal plates. The user then places the object to be weighed on one of the metal plates, and places weights of known value (not included in this particular artifact), on the other plate. Then the user turns the knob until the stoppers are no longer beneath the metal plates, and the plates are hanging freely. If the pointer hangs directly straight down, the load is balanced. If not, the process needs to be repeated by placing the stoppers beneath the plates again, then adding or removing weight in order to get the pointer to hang straight down. While the user is observing the pointer, it is important to close the glass door on the box to prevent airflow from impacting the results. The user will continue this until the pointer hangs straight down. Once the pointer is hanging straight down the user can sum the amount of weights added to the pan to find the weight of the object. The weight of the object is equal to the amount of added weight when the load is balanced.<br /><br /><a title="The Care and Use of a Balance" href="https://www2.humboldt.edu/scimus/Instruments/UseCareBal/UseCareBal.htm" target="_blank">The Care and Use of a Balance</a>
Stuart Gillette, Micaiah Grossmann, Sam Meluch, Nicholas Minarich, and Keeli Winquist
English
physical object
MCMT-9614 | R20770
These inscriptions could be make and model numbers, or relate to the manufacturing of the scale such as a serial number or tracking identifier.
USA
Nansen Bottles
oceanography; bathymetry; thermometry
Steven A. Walton and Robert Keen
1950s
physical object
English
USA
Mechanical Bathythermograph (MBT)
oceanography; marine biology; bathymetry
Steven A. Walton and Robert Keen
1950s?
English
physical object
USA
Ainsworth's Manual
Engineering
Robert A. Neault ('38) Collection
Steven A. Walton
1911
Text
English