236 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1947 



The petroleum industry has had its real growth along with two 

 other young industrial giants, the automotive industry and the avia- 

 tion industry. Further, although many of the new operations and 

 products which will come into our story later seem to have little or 

 nothing to do with either of these industries, the responsibility for 

 much of what has happened is closely tied with their growth. It all 

 began a little over 20 years ago when the automobile-engine designers 

 stopped worrying about whether their engines would start and con- 

 tinue to run, and began to be worried by their sales departments for 



50- 



40 



m 



UJ 



o 30 



UJ 



cr 

 2 2 



DEVELOPED 

 POWER 



POWER 

 REQUIRED 



LEVEL 



30 40 50 60 

 CAR SPEED - MPH 



FlQUBE 1. 



80 



promotional stories along the line of get-away, pick-up, hill-climbing 

 ability, top speed, and so on. These designers studied their engines 

 and their cars and found many interesting facts. Let us look into 

 a few of these. 



Figure 1 is a plot of horsepower against car speed for a typical 

 car of the time operating in high gear. The curve depicts developed 

 power as delivered to the rear wheels plotted against car speed. The 

 straight lines approximate power required to move the car at corres- 

 ponding speeds for level-road operation and for hill-climbing a reason- 

 able grade. All conditions of wind, fuel quality, and loading were 

 constant. It can be seen that this car has a top speed of 60 miles 

 per hour on the level and has a reasonable amount of excess power for 

 acceleration between the speed ranges of 15 to 60 miles per hour. 

 However, on the hill the car speed will drop off to a top of 40 miles 



