Home > Science Fact Finder > Time, Weights, and Measures - What Is A Bench Mark?

1. Printable Version
2. Download PDF
3. Cite this Page

What is a bench mark?

A bench mark is a permanent, recognizable point that exists at a known elevation (height). It may be an existing object, such as the top of a fire hydrant, or it may be an object specifically placed for measurement purposes, such as a brass plate on top of a concrete post. Surveyors and engineers find the elevation of objects by measuring, through a level telescope, the distance of a point from a preestablished bench mark.

Source: World Book Encyclopedia, vol. 2, p. 247.

Join eNotes

The above is a free excerpt. Get total access to this content with the:

eNotes Pass

1. Time
   1. How is time measured?
   2. What is meant by Universal Time?
   3. How many time zones are there in the world?
   4. Who establishes the correct time in the United States?
   5. What is military time?
   6. What do the initials a.m. and p.m. mean?
   7. When is Daylight Savings Time observed in the United States?
   8. What is a leap second?
   9. What is the exact length of a calendar year?
   10. Where did the term "grandfather clock" come from?
   11. What were the longest and shortest years on record?
   12. Besides the Julian and Gregorian calendars, what other calendars have been used?
   13. When does leap year occur?
   14. When did January 1 become the first day of the new year?
   15. How were the months of the year named?
   16. Where do the names of the days of the week come from?
   17. Why are the lengths of the seasons not equal?
2. Weights And Measures
   1. What is the metric system of measurement?
   2. What are the U.S. and metric units of measurement for area?
   3. How did the yard as a unit of measurement originate?
   4. What is a bench mark?
   5. How was the length of a meter originally determined?
   6. How are U.S. customary measures converted to metric measures and vice versa?
   7. What is the difference between a short ton, a long ton, and a metric ton?
   8. Why is a nautical mile different from a statute mile?
   9. What are the equivalents for dry and liquid measures?
   10. What are U.S. and British measures for volume and weight of water?

1. Augustus Caesar