Popular Science Monthly 



too 



position in one lA the- \ertical columns 

 allotted to the record for eacli lap. 



This la|) record shows the jiositioii of 

 each car within 60 seconds after it has 

 completed a lap, because not more than 

 a dozen car numbers are written on any 

 one sheet before it is torn ofT the pad 

 and passed to the visor and in turn to 

 the writers at the lap-sheet. 



Group No. 2, Checking Knowledge, is 

 made up of three men working two 

 machines, t)ne of which is a combination 

 of odometers, one for each car. These 

 odometers arc used to register t he mileage 

 covered by each car, so that b\- dividing 

 the reading as shown by the length of 

 the track in miles, one can tell the num- 

 ber of laps credited to each car. 



The other machine consists of two 

 rolls of paper which automatically un- 

 wind at one end and wind up at the other 

 b>' means of a crank attached to the 

 odometer. That portion of the paper 

 which is between the rolls is co\"ered 

 with celluloid except for a narrow slot 

 which pemiits a thin slice of paper to 

 show through. As the operators push 

 down the odometer lc\'er for an\- partic- 

 ular car, the man at the celluloid machine 

 marks tliat number on the paper showing 

 thnnigh the slot, and as the le\-er jumps 

 back to its original position, the paper 

 roll unwinds and brings a new strip of 

 paper across the slot. The record thus 

 obtained is used to check against the 

 odometer readings and the lap-sheet. 



The mechanism of Group No. 3, 

 Calculating Knowledge, consists of an 

 instrument known a$ the Horograph. 

 This is somewhat similar to the a|)para- 

 tus used on the railroads for notifying 

 a switchman that a 

 train is coming Ijy the 

 ringing of a bell as 

 soon as it has passed 

 over a distant section 

 of track. Electric 

 wires are strung from 

 the Horograph to tlie 

 finish line on the 

 track and as each car 

 passes over them, an 

 electrical contact is 

 made which actu- 

 ates a clock device 

 forming a part of the 



time of contact is automalicalK printed 

 on a long strij) of pajjer tape, similar to 

 that used, on stock tickers. This tape 

 feeds out o{ the machine along a narrow 

 table, as shown in the illuslralion oppo- 

 site, where it ma\- be examined with- 

 out being picked ui). 



Although tiie lime when each car passes 

 the finish line on each lap is printed on 

 the tape, the particular number of each 

 car is not designated, so that some 

 means has to be taken to connect the 

 time as shown with the car which makes 

 it. This is done l)y men stationed along 

 the table who watch the cars as they 

 pass and then mark the proper number 

 opposite each time record. 



Two men stationed along this table 

 take the time records from the tape as it 

 passes them and mark them on special 

 ruled sheets and then pass the sheets to the 

 round table wiiirli is shown adjacent to 

 the tape bench in the drawing opposite, 

 where two men operating adding ma- 

 chines calculate the speed in miles per 

 hour and reckon special lap speeds, for 

 which prizes are awarded. 



Directh- behind the calculators' table 

 is another which gives information to 

 the press and announces the winners to 

 those not in the stand. This is in 

 Group No. 4, Dissemination of Knowl- 

 edge. There is also another lap-sheet for 

 giving information to the scoreboard 

 and the grandstands. Many telephones 

 are provided for sending or getting in- 

 formation from the pits. 



T 



Backing an Automobile into a 

 Moving Garage 



II M illustration 

 shows a puzzle 

 recently placecL on 

 the market. In a 

 glass-covered circular 

 box two mo\able ob- 

 jects are enclosed. 

 They represent an 

 automobile and a ga- 

 rage, and the object 

 i^ to get them dove- 

 tailetl into each other. 

 The floor of the box 

 is of polished wood, 



It requires deft manipulation to get whlch makes the task 



apparatus so that the the automobile fitted into the garage more difficult. 



