Object Details
- Tacro
- Description
- The pointers on this German silver drawing instrument are held in place with screws, meaning that they can be adjusted and replaced. The points are 1-1/8" and 1/2" long. The front slide has scales for lines, running by ones from 1 to 10, and for circles, irregularly numbered from 6 to 36. Thumbscrews on both sides adjust the instrument along a gear and tooth mechanism (or "rack movement") on the back slide. The front slide is marked: TACRO INC. (/) GERMANY. The case is covered with black leather and lined with blue velvet. It is unlocked by pulling out a button on the right side of the case. The case is marked on the top: TACRO. It is also marked: 4130. The case is marked on the bottom: Made in Germany.
- Tacro is a manufacturer of drawing instruments apparently established in the 20th century. According to online auction records, it marked its products as made in West Germany from about 1950 to 1991. Thus, this object probably dates to the 1930s or 1940s. As of 2012, Tacro continues to make these proportional dividers.
- Location
- Currently not on view
- Credit Line
- Gift of Ursula N. Forbes
- ca 1940
- ID Number
- 1986.0316.02
- accession number
- 1986.0316
- catalog number
- 1986.0316.02
- Object Name
- proportional dividers
- dividers
- Physical Description
- aluminum (overall material)
- felt (overall material)
- wood (overall material)
- steel (overall material)
- Measurements
- overall: 2 cm x 22.8 cm x 3.8 cm; 25/32 in x 8 31/32 in x 1 1/2 in
- place made
- Germany
- See more items in
- Medicine and Science: Mathematics
- Science & Mathematics
- Dividers and Compasses
- National Museum of American History
- Subject
- Mathematics
- Drawing Instruments
- Record ID
- nmah_904358
- GUID (Link to Original Record)
- https://n2t.net/ark:/65665/ng49ca746a7-2f98-704b-e053-15f76fa0b4fa
