AMERICAN INSTITUTE. 537 



The key cannot be left in the lock, and is so small that there is 

 no inconvenience in keeping it in the pocket when not in use, 

 which prevents the burglar from taking impressions either from 

 the lock or key. 



4. There can be millions of keys made, and with proper care 

 there need not be two locks alike. 



5. The door is opened from the outside by simply pushing in 

 the key without turning. On the inside of the door it is opened 

 by pulling the knob without turning. 



It is considered by good judges as being the best lock for dwell- 

 ing houses ever introduced. There are in use in this and other 

 cities, several hundred of tliem, and in no case ha^e they failed to 

 give the very best satisfaction. 



In making a calculation on the weight of keys in use in this 

 city, we may safely assume that there are 250,000 keys of front 

 doors carried in the pockets daily; taking the average of the old 

 style of keys, we find they weigh about six to the pound, which 

 would give over 41,500 pounds of metal that the citizens of this 

 enlightened city carry in their pockets; and if we could calculate 

 the number of miles traveled, we would find that the amount of 

 power expended for that purpose is very great, besides the great 

 destruction of pockets, buttons, &c. 



With the key that is used for the rotary lock, that weighs 60 to 

 the pound, the weight would not be one-tenth as much; and if 

 used in place of the 250,000 mentioned, would effect a saving of 

 about 25 cart loads of metal, at the rate of 1,500 lbs. per load. 



Mr. Meigs was always very fond of looking back to the sources 

 of our knowledge, and examining all the countless trials, guesses 

 and experiments made by our contriving race before we attain our 

 , grand object. He reminded the Club of the extraordinary efforts 

 of one man of more recent note, and that is Mr. Tiftoft, Marquis of 

 Worcester, 200 years ago. The number 68 of his Century of Inven- 

 tions, is his invention of an Escutcheon lock, "Which the delicate 

 hand of a lady would lock and unlock, and which she could vary in 

 ten millions of combinations — beyond the knowledge ol the smith who 

 made it, or of me who have invented it. If a stranger openeth it 

 it setteth an alarm agoing which he cannot stop; and if no one 



