Wednesday, September 19, 2007



1091. Chinese knife money:

Other unusual types of Chinese currency include bridge and spade money.













1092. Current transformer, marked "Instruments & Accessories Company, model 31, 2-1/2 VA, USN Class GU, 50-400 cycles, XI, ratio 50/5, spec 3106, HI". These are used to reduce the amount of amperage sent to the ammeter for measurement.

When current is flowing through the primary of the current transformer, it is important to always have a wire between the secondary terminals. If these terminals are left open, dangerous voltages can develop and there is risk of electrical shock.


A photo of the inside:













1093. McGill Fastener Punch, used to make a hole in a stack of papers so that a brass fastener could be inserted. Similar to patent number 162,182.













1094. Still not sure what it's for, my guess is that it's either a specialized hook or a tightener for wire fences.



















1095. Knife sharpener, patent number 2,469,797
















1096. Photographer's instantaneous flash lamp, the interesting thing about this device is that it's ignited by a match hidden in the shaft. From the patent page:

The object of this invention is to so construct a flash lamp that it may occupy but a small space and may be readily carried in the pocket loaded for instant use...

Within the stem is fitted to slide a match holder...

...the thumb is pressed to cause the match-holder to be forced inward and the head of the match to contact with a means for igniting it at a point where the spark or flame therefrom will readily ignite the powder in the bottom of the bowl.

... the flash-powder being ejected from the bowl and diffused in the outer air, the lid of the bowl being thrown open by the explosive force and the atoms of powder ignited in the air after leaving the bowl...


Patent number 611,009



























To submit photos, click on the profile link at the upper right to find my email address.


















































Last week's set is seen below, click here to view the entire post:







Black Ops Pro Tips
More discussion and comments on these photos can be found at the newsgroup rec.puzzles.