| Name and Model Number | Collins Milk Scale by Brady & Martin, England |
| Country of Origin | England |
| Date of Manufacture | unknown |
| Front Scales | Temperature | Gravity Gerber | Solid percent |
| Back Scales | none |
| Scale Length | 5" (12.5 cm) |
| Type of Rule | Slide Chart |
| Construction | Boxwood |
| Area of Use | Other |
| Comment | Milk solids calculator.
Owner knows of only this example. Information on the company and some of their other products, most quite unrelated to slide rules can be found at: http://collectionsonline.nmsi.ac.uk/detail.php?type=related&kv=80442&t=people) |
| Rarity | RRR |
| Donor | Collection of Louis J. Gotlib, USA |
| Match Number | 22 |
| Thumbnail (Click Picture for Details) |  |
| In conjunction with our 'donors' we assign a rarity rating to each item, based on the system devised by Herman van Herwijnen |
| (1929 - 2004), renowned Dutch collector, author, and creator of Herman's Archive, a collection of 5,000 slide rule images on CD. |
| • RR = Rare - 1 of 25 collectors has one; it may take a year to find an example in the marketplace. |
| • RRR = Very Rare - only a few known to collectors; may be several years before it comes up for sale. |
| • RRRR = Extremely Rare - a museum piece; unlikely that an example will come up for sale. |