Davis Instruments Log Books/Reference Books
On-the-Water Knowledge, Built for Real Conditions
When you're underway, the last thing you want is to dig through a thick manual to find a critical rule or procedure. Davis Instruments has spent decades solving exactly that problem, distilling the most essential marine knowledge into durable, immediately usable log books and quick reference materials designed to live on the helm, in the nav station, or clipped to a bulkhead.
Davis Instruments, established in 1963, is a recognized leader in developing and manufacturing precision marine and outdoor instrumentation , and that same commitment to clarity and reliability carries directly into their reference book and card lineup. The company started its life in the 1960s as a marine product company specializing in lightweight plastic navigational tools , so producing reference materials that genuinely serve working mariners is deeply rooted in the brand's DNA.
Quick Reference Cards: The Core of the Lineup
Davis Quick Reference Cards offer a wealth of information on piloting, racing, navigation, marine electronics, marine life, and more in a handy, colorful, and easy-to-understand format. These aren't flimsy paper booklets — they're engineered for the marine environment.
Each Navigation Rules Card is full color on both sides and three-hole punched for binder or bulkhead mounting, and is also weatherproof and made from durable plastic, allowing it to withstand anything that comes your way. That construction detail matters enormously on a boat, where spray, humidity, and rough handling are facts of life.
Trusted by Professionals, Valued by All Boaters
Used by the US Coast Guard, US Coast Guard Auxiliary, and US Power Squadron, the Davis Instruments Navigation Rules card covers the US Buoyage System, Inland and International Rules, Right-of-Way, Lights, Sound Signals, Bridge Signals, zones of approach, distress signals, and how to recognize lights of different ships at night.
The range extends well beyond navigation rules alone. Davis reference cards include a complete Celestial Navigation system with sextant use and corrections, starfinder data for 18 stars, and weather forecasting using wind direction, barometric pressure, and cloud type — plus a full list of radio weather stations. Another card covers all basic boating procedures and equipment, including predeparture checklists, fueling, and piloting essentials like dead reckoning and position finding.
The Coastwise Piloting Quick Reference Card is a standout for coastal navigators. It puts all essential piloting information at your fingertips: dead reckoning basics, estimating distance off, position finding, true and magnetic compass relationships, and current and leeway corrections — plus a time/relative bearing gauge, distance and speed calculator, and common chart symbols.
Designed to Inform, Not Overwhelm
The information on each card is presented in a way that is legible and concise, with colors and shading helping to separate the different sections of information, making it easy to find exactly what you need. Boaters who have used these cards consistently praise their cockpit-friendly design — compact, weatherproof, and instantly actionable when conditions demand fast answers.
Whether you're a new boater building foundational knowledge or a seasoned sailor who wants a reliable quick-check resource at the helm, Davis Instruments' log books and reference materials represent some of the most practical and professionally vetted on-water documentation available today.