An hourglass or sandglass is an instrument for measuring a defined time and can be used perpetually by simply turning it over immediately the top bulb empties. The clear blown glass is shaped into two equal sized bulbs with a narrow passage in the centre and contains uniform sized sand or glass particles in the lower bulb. The width of the neck regulates the constant flow of the particles. The glass is held in a stand with top and bottom of equal shape and size. Hourglasses can measure an infinite variety of time by gauging the size of the particles, the shape and size of the bulbs and the size of the passage between the bulbs, thus measuring hours or minutes or even seconds. Generally an hourglass sits between discs of wood at the ends, which are joined by long wooden spindles between the ends and tightened by screw caps. The length of time can be adjusted by adding or removing sand particles. The use of the marine sandglass (or hourglass) has been recorded in the 14th century in European shipping. A one minute sandglass was used in conjunction with the ship’s log for ‘dead reckoning’, (see below) that is, for measuring the ship’s speed through the water. They were also used to regulate ringing the ship’s timetable; for example a 4 hour sandglass was used for the length of the sailors’ watch, and a half hour timer for taking of readings for the ship’s log; the ship’s bell would be rung every half hour. It was usually the role of the cabin boy to watch and turn the sandglasses over at the exact time of them emptying their upper chambers and to ring the ship’s bell. Hourglasses have been used historically for many hundreds of years. Some have been used for timing church sermons, in cooking, in industry and at sea. Even today they are used for measuring the cooking time of eggs and timing a player’s turn in games such as Boggle and Pictionary. The sandglasses at sea were gradually replaced in the late 1700’s to early 1800’s by the more accurate chronometers (marine clocks) when they became reliable instruments. DEAD RECKONING (or Deduced Reckoning) Dead reckoning is the term used to describe the method of calculating the ship’s position from its speed and direction, used in early maritime travel, mostly in European waters. Both the (1) speed and the (2) direction of travel were recorded on a Traverse Board at half-hourly intervals during a helmsman’s watch of 4 hours. The navigator would record the readings in his ship’s log, plot them on his navigational chart and give his updated course directions to the next helmsman on watch, along with the cleared Traverse Board. This was a very approximate, but none-the-less helpful, method of navigation. The wooden Traverse Board was a simple pegboard with a diagram of a compass with eight peg holes along the radius to each of the compass points, plus a grid with ascending half hours in the left column and increasing ship’s speed in knots in a row across the column headings, with a peg hole in each of the intersecting cells. A number of wooden pegs were attached to strings on the board. By placing one peg consecutively in the direction’s radius hole, starting from the centre, and the speed holes when the half hourly reading was taken, a picture of speed and direction for the whole 4 hour watch was created. (1) To measure the ship’s speed a one minute hourglass timer was usually used to measure the ship’s speed through the water and help to calculate its longitude. A rope, with knots at regular standard intervals and a weight such as a log at the end, would be thrown overboard at the stern of the ship. At the same time the hourglass would be turned over and a seaman would start counting the number of knots on the rope that passed freely through his hands as the ship travelled. When the timer ran out the counting would be stopped. A timer of one minute (one-sixtieth of an hour), knots spaced one-sixtieth of a nautical mile apart, and simple arithmetic easily gave the speed of the ship in nautical miles per hour ("knots"). This would be recorded every half hour. The speed could however be inaccurate to the travel being affected by ocean currents and wind. (2) To calculate the ship’s direction a compass sighting would be recorded each half hour.Marine hourglasses or sandglasses were used from around the 14th to 19th century during the time of sailing ships. This hourglass is representative of that era, which is during the time of the colonisation of Australia. Hourglass or sandglass; an instrument used to measure time. Two equal sized clear glass bulbs joined with a narrow passage between them, containing equal sized particles of sand grains in lower bulb. Glass sits in a brass collar at each end, in a frame comprising 3 decorative brass columns or posts, each attached top and bottom, using round screw-on feet, to round brass discs. Disc have Roman numerals for the numbers 1 - 12 pressed into their inner surfaces and hieroglyphics on the outer surfaces. Roman numerals on inner surface of discs " I II III IV V VI VII VIII IX X XI XII " Hieroglyphics impressed on outer surface of discsflagstaff hill, warrnambool, shipwrecked coast, flagstaff hill maritime museum, maritime museum, shipwreck coast, flagstaff hill maritime village, great ocean road, horology, hourglass, hour glass, sandglass, sand glass, timing instrument, dead reckoning, deduced reckoning, finding latitude at sea, sandglass with hieroglyphics and roman numerals, hourglass with hieroglyphics and roman numerals, brass hourglass

In 1902, William E Sessions and other family members purchased a controlling interest in the E.N. Welch Company, a clock manufacturer located in Forestville, Connecticut. Sessions' father owned a foundry located in the town of Bristol, Connecticut that produced cases for E.N Welch Co. On January 9, 1903, the company was reorganized and registered as The “Sessions Clock Company”. Within a few years the Sessions Clock Company was producing clock movements, cases, dials, artwork and castings for their line of mechanical clocks. Between 1903 and 1933 Sessions produced 52 models of mechanical clocks, ranging from Advertisers, large and small clocks with logos of various businesses, to wall, or regulator clocks, and shelf or mantel clocks, designed for the home. Many of the Session clocks from this period are prized by collectors. In 1930, the company expanded to produce electric clocks and timers for radios, while continuing to produce traditional brass mechanical movements. Beginning at the end of World War II Sessions W Model (electric) was widely used by various casting companies for their clocks. The dial of the W Model read Movement by Sessions. In the early 1950s Sessions begin to produce timers for television. In 1956, Sessions was absorbed by a company interested mainly in their timing devices. In 1959, William K. Sessions, grandson of William E. Sessions left the Sessions Clock Company and formed the New England Clock Company. In 1960, one of the Sessions Clock buildings was sold to the Bristol Instrument Gears Company. Kept as the Sessions Company, the new owners ran the operation until 1969 when changes in the market forced the Sessions Company into liquidation. In 1970, the remaining buildings were sold to Dabko Industries, a machine parts manufacturer.The item marks a time when clock production in America was at it’s peak producing clocks for sale in many countries, they were keenly priced, mass produced and available to all. The company had a relatively short life span life regards clock manufacture later diversifying into electric timer mechanisms. Yet it was perhaps inevitable with the advent of electricity along with stiff competition from other clock manufactures that would ultimately herald the end in 1935 of the Sessions company's ability to continue manufacturing mechanical clocks. Clock mantle type face set in a painted black case designed to represent a Greek building with gold decorative pillars. Free standing with decorative feet. No markings or inscriptions on clock case or mechanism flagstaff hill, warrnambool, shipwrecked-coast, flagstaff-hill, flagstaff-hill-maritime-museum, maritime-museum, shipwreck-coast, flagstaff-hill-maritime-village, sessions, mantel clock, clock, clock industries

This item was most probably used at the Ballarat School of Mines. Pajari Instruments Ltd. grew from a partnership established in 1945 when the first EX-AX surveying instrument that provided accurate azimuth and inclination was made available to the diamond drilling industry. The partnership between Charles Trotter and George Pajari Sr. was known as Trotter-Pajari Instruments and the EX-AX Instrument was dubbed the "TROPARI" by the diamond drilling industry. Charles Trotter, a mechanical engineer, was also a marketing genius who developed substantial demand in Australia, Africa and South America in the 1940's and early 1950's. In fact the sales to each of these continents exceeded those to North America during those early years. Pajari is located in Orillia, Ontario, Canada and offer services and products that assist customers with their individual requirements. After the death of Charles Trotter in 1956, George Pajari Sr. with the assistance of his wife Hilda continued the business under the title of Pajari Instruments. George Sr. set most of the tenets that comprise our present Mission Statement. If it wasn't user friendly or if it had to have experts to operate it, that instrument design was doomed. If the customer wasn't getting good value in his opinion, manufacturing and repair procedures were examined to see where efficiency could be improved to cut costs without sacrificing Quality. George Pajari Jr and his wife Darlene assumed the reins of Pajari Instruments Ltd. in 1981 when George Sr. decided on semi-retirement. George Jr. brought the "client geologist's" perspective to the company. The company moved from Toronto to a 30 hectare (80 acre) site near Orillia shortly afterward. This site provided the high magnetic latitude earth field environment without magnetic pollution that is necessary for accurate compass setting. The park like setting of this location is a positive psychological benefit for our staff. George Sr. passed away in 2002 being preceded by Hilda only by 3 months, George Jr. continues at the helm of the company. With dedication from long term employees/contractors and third generation family members, Pajari Instruments Ltd. continues operations/new product development in Orillia. (http://www.pajari.com/about.html) Brass levelling compass in green velvet lined hinged timber box. Known as a Tropari - a single-shot, micro-mechanical borehole surveying instrument operated by a timing device. Borehole direction is measured from the earth's magnetic field. The Tropari provides both direction and inclination which can be used to define the attitude of the borehole at the survey depth. Regular surveys at intervals as the borehole progresses will allow a plot of the borehole to be drawn from the data. The Tropari is easy to use and maximizes profits by minimizing capital and operational costs. The Basic Survey Train Consists of: PDSI / Tropari Container, 6m (20 ft) Nonmagnetic Rods, Impact Foot, and Connector at Top. (http://www.pajari.com/tropari.html) A sticker on the lid of the hinged box states: "A.E. Parsons 107 Leicester St., Carlton 3053 Telephone 347 5844"scientific instrument, compass