1434: The Year a Chinese Fleet Sailed to Italy and Ignited the Renaissance. Gavin Menzies
animals; chain pumps powered by horizontal water wheels; chain pumps operated solely by the current; rotary grinding mills operated by horizontal windmills; double-edged runner mills operated by horizontal water wheels; roller mills; cotton gins; and mills for grinding rice or corn. (See examples on pages in later chapters.)
Doubtless these descriptions of how to make a wide variety of useful farm machinery would have had value to farmers in other countries. Once the Chinese sailors were ashore, they could have supplemented their wages by selling these books, just as sailors in my time would sell cigarette rations to the locals or give their rum tots to pretty girls.
Another pocket encyclopedia, the Wu-ching Tsung-yao, a collection of the most important military techniques, gave detailed accounts of the construction and functions of a vast array of military machines. Here is Professor Joseph Needham’s translation of the text next to an eleventh-century description of how to make a flamethrower:
On the right is the naphtha flame thrower (fang meng huo yu). The tank is made of brass and supported on four legs. From its upper surface arise four vertical tubes attached to a horizontal cylinder above. They are all connected with the tank. The head and tail of the cylinder are large, (the middle) of narrow diameter. In the tail is a small opening the size of a millet grain. The head end has two round openings.
The description continues for another six lines before instructions are given for loading the machine:
Before use the tank is filled with rather more than three catties of the oil with a spoon through a filter (sha lo). At the same time gunpowder (huo yao) is placed in the ignition chamber at the head. When the fire is to be started one applies a heated branding-iron (to the ignition chamber) and the piston rod is forced fully into the cylinder.2
Subsequent instructions describe how to cope with misfiring or breakdown.
There are equally detailed descriptions of other military hardware in this remarkable book. The most formidable weapon described is a water-wheeled battleship dating from the Song dynasty (A.D. 960–1279). It details a twenty-two-wheeled ship commanded by rebels and an even bigger one owned by the government. “Against the paddle wheel fighting ship of Yang Yao, the government force used live bombs thrown from trebuchet catapults. For these they used pottery containers with very thin walls, within which were placed poisonous drugs, lime and fragments of scrap iron. When these were hurled onto the rebel ships during engagements, the lime filled the air like smoke or fog so that sailors could not open their eyes.”3
What is extraordinary is that this military information seems to have been unclassified—it could have been acquired by anyone. It must have been of considerable value to realms that lacked sophisticated gunpowder weapons in the 1430s, including Venice and Florence. Perhaps Chinese officers supplemented their incomes by selling these military pocket encyclopedias.
We can be confident that Zheng He’s fleets had every weapon then known to the Chinese: sea-skimming rockets, machine guns, mines, mortars, bombards for use against shore batteries, cannons, flamethrowers, grenades, and much more. His fleets were powerfully armed and well supplied by water tankers and grain and horse ships, which enabled them to stay at sea for months on end. In addition, the ships were repositories of great wealth—both material and intellectual.
Of equal importance were the calendars carried by the fleets. Given the order to inform distant lands of the commencement of the new reign of Xuan De, an era when “everything should begin anew,” a calendar was essential to Zheng He’s mission.
Today, calendars are little more than holiday presents—Pirelli Tire calendars, featuring beautiful women, gardening calendars awash with color, others that remind us of bank holidays, when to celebrate Easter and file our tax returns. In the 1430s, Europeans had no unified calendar, for they had not yet agreed how to mea sure time. The Gregorian calendar did not come into use until a century later. To Islamic people, however, a unified calendar was essential. The Muslim calendar was based on lunar months rather than the solar year. Each month had a different purpose, such as the month to make the hajj, the pilgrimage to Mecca, which began on the first day of the new moon. The Muslim calendar also provided the times of the five daily prayers.
The calendar was likewise of great political and economic impor tance to the Chinese, who for thousands of years had led the world in calendar making. In Ancient Chinese Inventions (page 67), Deng Yinke describes their meticulous approach.
In 1276 Kublai Khan, the first emperor of the Yuan dynasty, assigned the task of compiling a new calendar to astronomer Guo Shou Jing so that his new empire would have a unified calendar from north to south and the errors in previous calendars could be corrected. Guo was a scientist with an exceptional talent and dedication. On taking over the task, Guo said “a good calendar must be based on observations and observations depend upon good devices.” He went on to examine the Hun Yi (armillary sphere), the only instrument in the observatory of the capital Dadu (Beijing), and found that the North Star of it was set at 35° which was at the latitude of Kaifeng where the Hun Yi was made. This meant that the instrument had not been adjusted when it was transported to Dadu from Kaifeng…. Guo thus made it a priority to develop new devices. Within three years of strenuous efforts he worked out twelve astronomical devices which were far better in function and accuracy than previous ones. He also made a number of portable instruments for use in field studies outside Dadu.
As part of the calendar project, Guo presided over a nationwide programme of astronomical observations. He selected twenty-seven sites for astronomical observation throughout the country, which covered a wide area from latitude 15° N to 65° N and longitude 128° E to longitude 102° E. The items of observation included the length of the shadow of the gnomon, the angle of the North Star from the ground surface, and the beginning times of day and night on the vernal equinox and the autumnal equinox…. Guo also examined nearly nine hundred years of astronomical rec ords from 462 to 1278 and selected six figures from the rec ords for calculating the duration of the tropical year. Guo’s result was 365.2425 days, which was the same as that of the Gregorian calendar, the calendar now widely used across the world….
Guo Shou Jing and the other astronomers worked for four years and completed the calendar in 1280. They made numerous calculations converting the data of the ecliptic coordinate and the equatorial coordinate systems, and used twice interpolations to solve the variations in the speed of the sun’s movement, which affected the accuracy of the calendar. The calendar was unpre ce dented in accuracy. It adopted the winter solstice of the year 1280, the ninth year of the Yuan dynasty, as the epoch, the point of reference for the calendar, and established the duration of a tropical year of 365.2425 days and that of a lunar month 29.530593 days. The error between the duration of its tropical year and that of the revolution of the earth around the sun was only 26 seconds. The calendar was named the Shoushi, meaning “mea sur ing time for the public.”
Issuing calendars was the prerogative of the emperor alone. Accuracy was necessary to enable astronomers to predict eclipses and comets—a sign that the emperor enjoyed heaven’s mandate. If predictions proved incorrect, the astronomer responsible was severely punished, often with death.
The Shoushi calendar produced by Guo Shoujing was officially adopted by the Ming Bureau of Astronomy in 1384. This is the calendar that Zhu Di and the Xuan De emperor would have ordered Zheng He to present to foreign heads of state (discussed in detail in later chapters).
The Shoushi calendar can be viewed in the Yuan shi-lu, the official history of the Yuan dynasty. However, copies also came into the possession of Europeans, notably the diarist Samuel Pepys and the famous scientists Robert Boyle and Robert Hooke. The Japanese and Koreans also copied the calendar, and translations from those languages can be viewed on our website.
The calendar contained the length of a solar day at the latitude of Beijing. This is the duration from the time when the sun is at its maximum height (altitude) in the sky from one day to the next. We tend to think of this as twenty-four hours. It is not. The earth rotates around its own axis