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Review Essays of Academic, Professional & Technical Books in the Humanities & Sciences


Magnetic Compasses

Compass Chronicles by Kornelia Takacs (Schiffer Publishing) After the invention of the magnetic compass and its first use in Italy for travel in the 16th century, a ship's course could be constantly monitored, leading to exploration and world trade. This intriguing guide explores a wide range of fascinating pocket compass types. Examples shown date from the late 1700s to the 1940s, with a focus on the mid-1800s and early 1900s. Hundreds of compasses are discussed with 507 colorful illustrations and detailed descriptions. The history of their development is explored, special uses for the U.S. Engineering Department and civilian groups are presented, and patented improvements are featured. Cases for compasses include wood, leather, and brass in distinct styles around the world. The variety of craftsmanship quality, style, and value can help to identify origin and make collecting enjoyable and rewarding.

ABOUT THE AUTHOR Kornelia Takacs was born and raised in Budapest, Hungary. She became fascinated with pocket compasses in 1998 and spent the next decade collecting and researching these unique and elusive instruments. She currently resides in Los Angeles, California.

Compass Parts lexicon

Excerpt: Pocket compasses are intriguing. They are relatively simple in construction, but quite elegant. Their variety of styles is expressed in the skill and craftsmanship that was an essential part of their creation. They are practical, unique, and metaphorical. Who would have thought that there were so many different pocket compasses? I certainly did not imagine the incredible variety when I first became interested in the subject.

The invention of the magnetic compass was important to the development of Western civilization. It forever changed maritime life and much more. The exploration of the unknown world became possible as explorers could make voyages of discovery and travel farther, while keeping a detailed log of their journey's course. The magnetic compass revolutionized maritime trade as well. Trading ships could sail from port to port on a fixed course. Navigators no longer needed to rely on clear skies to determine the ship's direction. The ship's course could be monitored with the help of the magnetic, directional compass.

The origin of the compass has been traced to China, although the Chinese did not use the compass to navigate on land or sea. Its first appearance for determining direction for travel was arguably from Italy. Several publications referred to in the bibliography discuss the invention and history of the compass. This book is a guide through the wide range of pocket compasses, with colorful illustrations and detailed descriptions to demonstrate examples and fine specimens. Various types of magnetic compasses are included, such as escape, wrist, fob, and sundial compasses to name only a few.

The majority of the compasses described in this book were manufactured between the mid-1800s and early 1900s. Examples reach back to the late 1700s and also cover many models that were produced in the 1940s. Many of the antique pocket compasses that one can find do not appear here. This work is far from complete, but it is a first step in the right direction.

It is hoped that this book will inspire readers who find these elusive instruments interesting and feel compelled to find out more, and still be enjoyable to the serious collectors who seek detailed information about specific models.

Several hundred different compasses are presented within the covers of this book. The majority of the high quality compasses have a bar needle, jeweled pivot, and a needle lock. Compasses listed will have all three of these components unless the description specifically states otherwise, such as a flat needle, brass pivot, and no needle lock. Dry card models state if they have a needle lock or not, because the dial obstructs the view of the needle lock. All compasses shown have a glass crystal, even the small fob and escape compasses.

An open-faced compass generally has a pendant. The pendant is the encompassing term for the bow, release button, and the crown. The compass dial is visible at all times. The case has no hinged, protective cover.

The hunter cased compass has a pendant and a hinged protective cover. The hinged cover is closed when the compass is not in use, providing valuable protection to the crystal.

The half-hunter case has a small glass window fitted into the front cover. A pebble glass was also used and this acts as a magnifier glass. This improvement made the half-hunter case useful for tradesmen who could inspect their goods easier with the use of their pocket compass. Half hunter pocket watches allow the time to be read without having to open the watch. Half hunter pocket watch style compasses were manufactured in limited numbers.

Fob or charm compasses are small compasses that can be attached to a pocket watch chain. They were also sold as jewelry charms and worn on necklaces.

The needle lock or transit lock is a slim metal bar that lifts the pivot off the central pin to prevent unnecessary wear on the pivot when the compass is not in use. One end of the needle lock rests on the center of the compass rose, around the central pin. The other end of the needle lock is most often located beneath the hinge on hunter cased models. As the cover is closed this metal bar is lifted up at the center of the compass dial and with it, it lifts and holds the brass or jeweled pivot up against the inside of the crystal. On open-faced models the needle lock may be activated by twisting the bezel or by rotating, pressing down, or pulling the stem. On dry card and most enamel dial models the needle lock runs beneath the dial. The majority, but not all jeweled pivot compasses have a needle lock. Many of the early, high quality brass pivot compasses and some of the early 1900s lower quality French made compasses contain a needle lock.

Lubber line is a term for a vertical line on the inside edge of the compass case adjacent to the dial. Quoting from an 1861 compass related article: "In marine compasses there is a notch cut in the brass case in which the card and needle vibrates. This notch is called "Lubbers' point" and it is set in a line with the ship's head, and it indicates the course the vessel is steering according to the point in the card nearest to it." Pre-1900s, round, brass-cased, and Singer's Patent compasses often bear this "lubber line" mark.

Compass patents. Innovations are crucial to any field and compasses went through their changes with time. Existing designs and models were modified and improved. New, more precise concepts and designs were created from scratch. Singer's distinctive black and white compass dial patent, revolutionized the dry card dial in the 1860s. Schmalcalder came up with his groundbreaking prismatic compass patent in 1812. Other compass patents, such as Hunter's and Symons's, are more obscure, catching the eyes of people who are familiar with compasses. Unique patent drawings and information, when available, are found throughout this book.

Luminous vs. Radium paint. Many compass dials contain a substance that renders these instruments visible in low light. A brief description from an old catalog, of the two different materials that were commonly used: "This material (meaning radium) is not to be confused with the old luminous paint so often used on signs, clocks, etc. Luminous paint had to be exposed to sun light for the purpose of absorption and after dark it would remain luminous for a few hours. Radio active compound (meaning radium) need not be exposed to the light and will remain active indefinitely." (A Geiger counter can help gage the status of compasses that contain radium paint. Military models tend to contain more radium paint compared to non-military, pocket compasses.)

Dial graduations are the lines that are seen on the edge of the compass dial. Four- and eight-point compass roses, drawn on old maps were ideal for the general orientation of the map-reader in relation to the map; however the compass dial required more detailed and precise markings. Dials are very often marked in a numerical order. Not all dials are numbered from 0 to 360, many are marked in quadrants. Numbered is the term for the numbering system that is seen along the edge of the dial in accordance with the graduation markings. Not all compass dials are graduated and, or numbered. The Singer's Patent dial, for example, generally contains a 32-point compass rose without graduation or numerical markings.

Quadrant markings are quite common on pocket compasses. Quadrant is the term when the dial is numbered in four different sections. Starting from North towards East it is marked from 0 to 90 degrees. From East towards South it is 90 to 0 degrees. From South towards West it is 0 to 90 degrees and from West to North it is marked 90 to 0 degrees.

The flat, blue needle was used during the 1800s. The early, blue, cross-type needles generally have a brass "crown" pivot. The slim, blue needles with a gilt "N" and "S" on the appropriate sides of the needle have either a brass "crown" pivot or a high quality, round brass pivot. From the early 1900s the flat needle style was generally used on lower quality compasses. The shape was easier to stamp out and magnetize compared to bar needles. (There are several, high quality exceptions including French and American compasses.) The 1900s flat needles are generally blue on the North half.

The bar needle requires careful construction and workmanship. Generally the North tip of the needle is identified with a small metal piece pierced through it or a small piece of wire coiled around it. (This weight also helps to keep the needle horizontally balanced.) Bar type needles are generally accompanied by jeweled pivots and are used in high quality compasses.

Jeweled and brass pivots. The pivot of the compass needle balances on a pin that protrudes from the center of the compass dial. The center of the pivot is the part that makes contact with this pin. Often a cut and polished "jewel" or "agate" is inserted into the center of the brass pivot. The term "jeweled pivot" is sometimes referred to as an "agate cap." Jeweled pivots are generally red, occasionally clear or white. Jeweled pivots are more durable compared to brass pivots and usually imply a higher compass quality. Mid-1800s "crown" brass pivots are high quality. Crown pivots were used in a variety of compass styles. The majority of brass pivots produced after the 1880s are lower in quality.

The fleur-de-lys, is a stylized lily that originates from France. England also adopted this symbol, which has become synonymous with the compass rose. The large majority of compass roses bear a fleur-de-lys design to represent North. Compass dials used to also mark the East cardinal point with a fleur-de-lys. The use of this "Decorated East" marking began to taper off around the 1850s to 1860s.

The dry card compass is also known as the "floating card" or "floating dial" compass. Dry card dial compasses were produced in England in the largest numbers. This term does not specify weather a compass is liquid filled or not. It only refers to the fact that the compass has a rotating dial instead of a visible compass needle. A flat magnetized bar containing the central pivot is attached to the bottom of a round disk. The disk is then placed onto the central pin in the same fashion as the regular compass needle. As the magnetic bar moves, the viewer sees the whole card rotate as it settles into position. A spot of wax on the opposite side of the compass rose was commonly used to balance the dial. The needle lock runs beneath the dial. Dry card dials generally use a 16, 32 or 64 point compass rose.

Larger ships' compasses went through changes as well. Circa 1600s compass dials often depict a wide array of detailed, colorful drawings of extravagant mythical sea creatures, cherubs and other characters. The dry card compass dials remained quite elaborate for several centuries. By the 1800s, due to increased production, these colorful dials were replaced with a more subdued, black and white pattern.

Several compass designs utilize dry card compass dials including round, brass compasses with a press fit cover, open-faced, hunter cased, fob and even some escape compasses. The dials during the 1800s were made of paper, occasionally from mother of pearl. Starting around the early 1900s dry card dials were made of aluminum. During the 1800s, dry card dials generally had a black and white design. During WWI and WWII many British pocket compasses used the Dennison dial design.

The black and white compass dial designs varied noticeably. There are several distinguishable patterns that stand out and can be easily recognized. Singer's patent is probably the most prominent and enduring example. Other designs include Symons's Patent , Hunter's Patent, Patent Universal and the Royal Geographical Society pattern . This latter design was favored on early 1900s British private purchase compasses and in wire lug wrist compasses.

The 1871 edition of the Royal Geographical Society's book, Hints to Travellers by Admiral Sir George Back, F.R.S, Vice-Admiral Collinson, C.B., and Francis Galton, Esq., F.R.S., shares some insights about pocket compasses followed by an illustration:

Pocket Compasses.- The patterns on these cards have been greatly improved of late years. Until recently it was scarcely possible to meet with a compass capable of being read in a dim twilight, which is just the time when it is of most importance to a traveller. Representations of three cards, each of which has its advocates, are given here. They are of the larger size, being 2 inches in diameter. Fig. 3, called the Rob Roy Canoe pattern, is decidedly less distinct in the twilight than the others, especially than Fig. 1, but some travellers have preferred it on account of the legibility of the N.E., S.E., Etc.

The better cards are made either of talc covered with paper, or of mother-of-pearl. Both of these materials are heavy and their weight, of course, tends to injure the point on which they turn, especially if they happen to receive a jar when they are resting on the point, and also to make their oscillations sluggish. These disadvantages are, however, less serious than those which attend the use of a common card, which warps with heat, and is spoiled by a wetting.

A pocket compass suspended on gimbals practically comes to rest much more quickly than one that is held in the hand. This advantage is specially noticeable when it is growing dark, and when consulted on the side of a hill, for in either case it is difficult to judge of horizontality. It is most important to a traveller, whose caravan is on the march, that he should lose very little time when he is consulting his compass.

Mem.- To read a compass or a watch in the twilight, when it is a little too dark for unaided vision, use a strong magnifying glass. Its effect in giving distinctness is extraordinary. -F. GALTON.









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