Actually -- those numbers on the top angle of the rack were either indicated by a pointer in the projector, or viewed through a window in the projector -- so you could slide the carrier along until a specific slide was in position to be loaded and projected. Stacked had nothing to do with it, since you don't care what number is where when there are multiple carriers stacked up -- only when there is a carrier in the projector, or when you have a carrier in your hand and wish to pull out a specific slide. There is typically a clear plastic dust cover which snaps over the carrier when it is not in the projector, and there is a label on which you can write a very short description of each slide by number to help you find the one you want.
In later carousel trays there are similar index numbers around the skirt for quickly rotating the carousel to position a specific slide for projection.
Where is "here"? And which temperature scale? C or F? I'm currently in Northern Virginia, and it is sort of hovering a bit over the freezing point.
But the place which I was describing was deep South Texas. Close enough to the border so you start to experience the exponential spice rise as you approach the border (from either side). :-)
There, the ability of a breeze to flow under the floor is beneficial most of the year. Up in North Dakota, it is something which you certainly don't want to happen. :-)
REAL Upstate NY (as opposed to the folks who think that 10 miles north of NYC is upstate) Fahrenheit scale, Oh and it has dropped just a bit, it's about 6 outside at this time.
1465 resembles a weather vane, but a weather vane does not indicate speed or exact direction. If this device were to measure wind direction, I would expect it to have a short, heavy head, a long tail with lots of fin area, a pinpoint pivot for low friction, and little capability for balance adjustment.
Was a separate instrument to be carried to measure speed? A measured length of thread and a lightweight ball of a standard size and weight can be used to measure wind direction and speed precisely. You hang the ball in the wind and use a plumb bob to mark the ground below the ball and below the suspension point.
I think the pivot was designed not to be moved by a light wind. The fitting in the middle of the arrow shaft adds considerable mass below the arrow shaft. If the internal pivot point is near the top of the fitting and the hole in the fitting is conical, screwing the weight along the arrow shaft could adjust the slope at which the arrow balances, pointing several degrees up or down.
If your eye is a couple of feet behind the arrow and you move your eye until the horizontal fins of the head are centered with the vertical tail fins, you will see exactly where the arrow is pointed.
Now suppose you have a paper frame (a paper rectangle with a rectangle cut out to fit snugly around the brass rectangle with the two thumb nuts). Suppose the paper frame is printed with degree markings, with zero at one corner and going clockwise like a compass. Put that paper frame on the wood, around the brass, with the zero corner of the paper at the south corner of the brass.
I think the arrow was designed to be read at the tail because it's easy to align your eye above the vertical fins. Because the paper frame is
180 degrees out, the mark below the tail will be the direction of the head.
A reason to read from the tail is that that's where the person who aims the arrow will be. A reason to use paper is that marks printed on clean paper will be easier to see than marks on brass or wood. A reason to use a square instead of a circle is that the paper will be perfectly aligned when fitted around a square.
Before a battle, the general has one of these instruments at his HQ. Two spotters also have them. One goes up a hill on the left and the other goes up a hill on the right. All set up their boxes. The spotters write their azimuths to HQ and the guy at HQ writes his azimuths to them.
Then the spotters document the battlefield, listing azimuths to military positions, churches, houses, bridges, stone walls, etc. I think these instruments could be dependable to a degree or less.
These azimuths could be used to map the battlefield so that the general can see the significance of battle reports and so the artillery can see where to shoot.
Set up by magnetic compasses, the boxes will probably not be aligned closely enough to plot accurately. That's where the front-back sightings come in. If the guy at HQ sees a spotter at 280 and the spotter reports HQ at 99, the guy making the map knows to add a degree will know to add a degree to all that spotter's azimuths. If he also corrects the other spotter's azimuths, he can make a good map.
"E Z Peaces" wrote: (clip) Before a battle, the general has one of these instruments at his HQ.
^^^^^^^^^^^^^^^^^^^ The procedure you have outlined would work, but I can't believe anyone would build an instrument for sighting directions, and not have the measuring scale next to the pointer.
The first item is a portable binnacle box for small vessels not permanantly equipped with them inthe old days.
I have one but it also has a box top that fits over it and has latches on the sides to hold the cover on.
The cover also has a handle to carry it by.
They would be mounted on a pedastal similar to the binnacle on an old sailing ship, or eve more modern vessels.
The other piece with the handle on top is the companion light that is shaded to allow a bit of light on the compass but not destroy the night vision.
I have also seen that pliers looking gadget. Our electrians all had one to bend heavy gage wire. Not sure if that is what it is for but it sure worked good.
Ease of accurate reading. Degree marks would have been about a millimeter apart. I have a ruler with black mm marks on white plastic. I have a steel tape with black mm marks on yellow enamel.
If I had to go up a hill and read how the tail of the arrow lined up with mm marks on the brass of that instrument, I would prefer to read against black marks on a white surface. In those days, printing the marks on paper may have been more practical than painting them on enamel on brass.
As much as possible, battlefield equipment should be durable, cheap, easily portable, and foolproof. I think theodolites would have been impractical.
Delicate mechanisms to get out of whack.
Lenses to get damaged, dirty, or misaligned.
Expensive.
Big and heavy, especially with the tripod.
Require expertise.
I've used several expensive compass models for preliminary surveys or to locate sighted items on maps. I've found them almost useless.
The most expensive advertised accuracy to 0.5 degree. That requires a spindle that's precisely centered. To check, I taped a paper to the top of a metal-free table, drew a line on the paper, and marked a dot on the line. This was a means to rotate a compass with square sides 90, 180, and 270 degrees and put it down exactly where it had been. I found front-back discrepancies up to 2 degrees. The spindle wasn't centered precisely enough for the advertised accuracy.
The next test for a compass is sighting accuracy. I would put a fiberglass fence post in a field as a stable, level base for a compass, then try several sightings to another post. I could not sight a compass consistently to a degree.
The next test was to erect three posts in a line and put a compass on the middle post to compare front and back directions. None of my compasses was satisfactory.
The last test was to erect four posts in a hundred-foot square in a field with no visible metal nearby. That would give me 12 readings to compare. The discrepancies were worse than ever, indicating that moving a compass a hundred feet can change magnetic north.
Item 1465 appears to be cheaper, easier to carry, more durable, and more foolproof than a theodolite. Instead of depending on the precision of compass readings, it would depend on a comparison with readings of other such instruments.
Is yours any different from this one? To steer a boat, wouldn't you have to remove the tower to see the compass? Wouldn't the cardinal points on the tower be correct only if you steered in a certain direction?
What would the arrow be for? I've seen one binnacle box with a tiny telescope to take bearings to landmarks, but it appears that aboard a boat the arrow would get knocked off or poke somebody in the eye. Why would it need a major adjustment for balance?
Now that you mention it, the cover is curious. Luminous paint was in use by 1903. Before that, if I wanted to read a compass in low light, I think I'd want a large white rose with a few bold black marks.
1465: Portable weathervane. Perhaps this one was intended for dueling purposes (ensuring neither side has the advantage of the wind), considering the two pistols; you wouldn't need the compass for that, though.
Four of the six have been answered correctly, on the remaining two I would bet that the correct ID is probably among the guesses, but they are difficult to prove one way or the other right now.
Thanks for the link, though I have to admit I was disappointed when I went to Google maps and found the Circleville wasn't laid out in a circle, then I went back and reread the page where it said that it "derives its name from the fact that the original town was laid out within a circular enclosure, formed by a high embankment, that was found here when the first settlement was made." I really expected a circular street with straight roads radiating out from it, seems like false advertising to me.;-)
The ice card was hung in the window. That way the iceman could see it from down in the street. Even if he could not read the numbers, if his eyes were going, or you were on the fourth floor, he coould see the color, knowing that red was 20 lb, etc.
You DO remember how Jack Benny described his eyes, don't you? "Blue. Bluer than the right shoulder of a left-handed iceman."
Probably in reference to the poor schlub who had to haul sixty pounds up three flights of stairs, at every third house in south Chicago.
Item 1470 is definitely a jack and could be used for a number of purposes. The item is exactly like the machinery jacks I use to set up odd shaped parts on a machine so they can be cut except that mine don't have the fancy designs on them.
Were those the ones made by Starrett? They had two sizes, with the 1-1/2" one being the smaller. The came with two screws -- one with a conical point, and the other with a tilting pad on a ball. The top just above the thread was square, with two holes at right angles going through the square for tommy-bars for actually adjusting them. They also had (in the full set) a cylindrical spacer to extend the height, another such spacer with a 'V' in the bottom to place over a round rod, and a third one with a blunt chisel to fit into a V.
Check out eBay auction # 220315381867 for a good set of photos of a pair of them.
Of course -- Starrett was not the only maker, just the most popular -- and they were shop made as well.
They were used on shapers, mills, and planers to support an irregular casting so the surface to be cut would be parallel to the travel of the cutter.
I've found that 1465 wouldn't have been for mapping battlefields. To make reconnaissance maps, soldiers used plane tables as surveyors did.
In Europe, theodolites came into use for collecting data as numbers instead of maps. They weren't very useful in America because woods obstructed lines of sight. Not even Lewis and Clark carried one.
In Philadelphia, William J. Young invented the transit in 1831. It was more useful than the theodolite because the telescope could be flipped to extend a line.
Because America had little capacity to build such instruments, Young contracted with a British manufacturer to make 36. Most were unusable. If they were so hard to manufacture, they must have been expensive and hard to get fixed. That may explain why American surveyors depended largely on compass readings, as George Washington had, until 1880 or later.
A surveyor's compass was called a circumferentor. It was attached to the top of a staff. The surveyor would sight, then read his compass. Surveys were inaccurate because magnetic north changed from point to point. I doubt it would have been accurate even to measure an angle. The spindle would have to be precisely centered in the card. Any friction would interfere with consistent settling of the needle. Iron carried by the surveyor could also interfere.
In that context, 1465 looks to me like an American answer to the theodolite. It would have been easy to manufacture, cheap to buy, and easy to service.
Polished brass has a high contrast to tarnished brass or brass blackened with sooty smoke. Polishing only the head of the arrow and the top edge of the tail vane could make it easy to aim the head and read the tail as an indicator.
Printed paper was popular for compass cards in the 19th Century. The card may have been a replaceable square border of paper around the brass base. (The square shape would prevent misalignment.) The card may have been higher, on a structure secured by the thumb nuts.
I think 1465 was placed on a sort of three-legged stool about four feet high, in the manner of a plane table. There's a sort of "lugnut" at the top of the spindle. The flat top of the "lugnut" is about 6 mm wide. At arm's length, that would be about half a degree. You'd center the target on the top of the spindle.
The arrow head is only a couple of mm wider than the "lugnut". If you reach out and nudge the tail until the edges of the polished head are visible on both sides of the "lugnut", that will align the arrow with your line of sight, to the target. Now, if the top edge of the tail vane is polished and the sides are black, you can get consistent readings on the card by positioning your eye above the tail vane where you see the brass top edge but neither black side.
I think the screw weight is a friction adjustment. You'd want the arrow to respond to a light nudge but not a gust of wind. I think with the weight closest to the spindle the arrow would balance, for minimum friction. Screwing the weight toward the head would increase friction between the spindle and the hole in the brass post.
If you were starting a survey with no azimuth for reference, you could orient the instrument by aligning the cross with the compass needle. If you had an azimuth for reference, you could set the arrow to the desired card reading, then orient the instrument by rotating the base to aim the arrow.
The spindle must be centered on the card to give accurate readings. This could be checked by setting the instrument on line between two targets and comparing readings to both targets, then repeating the process with the base rotated 30, 60, 90, 120 and 150 degrees. If there were deviations, this would tell the surveyor which way the brass post was tipped and how far. Pressure on the post could correct this by bending the metal cross slightly. That could be more practical than sending an instrument away for service. The cover, which looks tall enough to latch on without removing the arrow, was probably intended to protect the post from being pushed out of alignment.
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