hydraulics slide chart
Date: ca. 1940-1970
Inventory Number: 1997-1-1616
Classification: Slide Rule
Subject:
Maker: Robert E. Martin
User: Gordon M. Fair (1894 - 1970)
Cultural Region:
Place of Origin:
City of Use:
Dimensions:
0.2 × 15.2 × 15.2 cm (1/16 × 6 × 6 in.)
Booklet: 0.3 × 18.6 × 16 cm (1/8 × 7 5/16 × 6 5/16 in.)
Accessories: manila envelope
DescriptionTwo plastic discs, one blue and one white, and a clear plastic cursor with indicating line, joined at the center by a brass fastener.
A number of scales are printed on the smaller top disc. Around its outside edge are two scales: an "L" scale and a "V" scale. The "L" scale has values descending from 20M' to 100'. Around the mark for 1M is an arrow pointing outwards. The "V" scale has values descending from 42'' to 4''.
Just inside the "L" scale is a logarithmic "F" scale carrying values from 0.1 to 10. Inside this is a slot through which a scale printed on the bottom, larger disc is visible. That scale has values ranging from .06 to 250. Printed on the smaller disc just above and below the slot are two arrows, pointing towards the slot. The bottom arrow is labeled, "1.85 H/Q".
Inside the "F" scale on the smaller disc are a series of short, spiralling scales for "C AND D". Each scale is labeled with one of the following values: 72'', 42'', 36'', 30'', 24'', 20'', 18'', 16'', 14'', 12'', 10'', 8'', 6'', 4''.
Three scales are printed around the circumference of the bottom, larger disc. Adjacent to the smaller disc is a logarithmic scale for "MGD AND V", with values ranging from 0.1 to 10. Outside this is a scale for "GPM", with overlapping values ranging from 45 to 6500. Near the outside of the disc is a logarithmic scale for "H", with values ranging from .06 to 250.
Printed on the back of the larger, bottom disc are instructions for the slide chart's use, as well as a list of factors used in converting a pipe's dimensions to set C = 100.
The slide chart is stored in a manila envelope.
A number of scales are printed on the smaller top disc. Around its outside edge are two scales: an "L" scale and a "V" scale. The "L" scale has values descending from 20M' to 100'. Around the mark for 1M is an arrow pointing outwards. The "V" scale has values descending from 42'' to 4''.
Just inside the "L" scale is a logarithmic "F" scale carrying values from 0.1 to 10. Inside this is a slot through which a scale printed on the bottom, larger disc is visible. That scale has values ranging from .06 to 250. Printed on the smaller disc just above and below the slot are two arrows, pointing towards the slot. The bottom arrow is labeled, "1.85 H/Q".
Inside the "F" scale on the smaller disc are a series of short, spiralling scales for "C AND D". Each scale is labeled with one of the following values: 72'', 42'', 36'', 30'', 24'', 20'', 18'', 16'', 14'', 12'', 10'', 8'', 6'', 4''.
Three scales are printed around the circumference of the bottom, larger disc. Adjacent to the smaller disc is a logarithmic scale for "MGD AND V", with values ranging from 0.1 to 10. Outside this is a scale for "GPM", with overlapping values ranging from 45 to 6500. Near the outside of the disc is a logarithmic scale for "H", with values ranging from .06 to 250.
Printed on the back of the larger, bottom disc are instructions for the slide chart's use, as well as a list of factors used in converting a pipe's dimensions to set C = 100.
The slide chart is stored in a manila envelope.
Signedback of bottom disc, bottom right: HYDRAULIC CALCULATOR / Robert E. Martin / CONSULTING ENGINEER / Louisville, KY
Inscribedface of top disc, just above top fastener: HYDRAULIC / CALCULATOR ;
face of envelope, bottom center: THE HYDRAULIC CALCULATOR
face of envelope, bottom center: THE HYDRAULIC CALCULATOR
FunctionFor use in calculating the slope, total loss in line, or velocity of pipe flow. Instructions for each operation are printed on the back of the bottom disc.
Curatorial RemarksSee an earlier version of this slide chart, 1997-1-1614.
ProvenanceFrom Prof. Gordon Fair's office in Pierce Hall (Harvard University Engineering and Applied Sciences) 5/5/70.