The Study of Jyotisha · Chapter 42 of 54 · Part Eight · The applied branches

#Samhita: omens, weather and the world

#The third branch

Chapter 1 described the three branches (skandhas) of Jyotisha: ganita (astronomy and calculation), hora (horoscopes of persons) and samhita (everything else: the sky's signs for kingdoms, the weather, omens, and the practical knowledge of daily life). This course has mostly been about hora. This chapter introduces samhita, through its greatest book: Varahamihira's Brihat Samhita ("the great compendium"), which N. Chidambaram Iyer translated into English in 1884.

The Brihat Samhita is an encyclopaedia. Its 106 chapters cover the Sun, Moon and planets; eclipses, comets, meteors, halos, rainbows and earthquakes; rain, winds and crops; the prices of goods; the geography of India; building houses and temples; finding water underground; gardening; images of the gods; the signs of good horses, elephants, dogs, swords and gems; the features of men and women; perfumes; and many kinds of omens. It is one of the most important sources for the knowledge and daily life of sixth-century India.

#The scientific Varahamihira: eclipses

The chapter on Rahu shows Varahamihira at his most rigorous. He begins with the popular stories: Rahu is the severed head of a demon who swallows the Sun and Moon; or a serpent; or darkness itself (Brihat Samhita 5.1–3). Then he asks pointed questions. If Rahu has a body moving in the zodiac, how does he eclipse the Moon when it is 180° from him? If there are two Rahus, how is the Sun seen uneclipsed opposite the eclipsed Moon (5.4–7)? And he gives the answer:

The truth is that in her own eclipse, the moon enters the shadow of the earth, and in that of the sun, [the moon covers] the solar disc (Brihat Samhita 5.8).

Thus the causes of the eclipses have been stated by learned astronomers; that Rahu does not cause the eclipses is the truth of the shastras (5.13).

He explains why lunar and solar eclipses begin on opposite sides of the disc, why a solar eclipse looks different in different countries, and why the eclipsed Moon's horns are blunt and the eclipsed Sun's sharp (5.8–12). He rejects two popular methods of eclipse prediction — that an eclipse needs five planets in conjunction, and that it can be foreseen from a drop of oil on water (5.17) — and refers to his astronomical work for the calculation (5.18).

Then, in the same chapter, he turns to the meaning of eclipses for kingdoms and crops (5.19 onward). Both sides — the astronomy and the omens — are part of the same book. This is typical of the samhita: careful observation and calculation stand next to traditional interpretation.

#Rain

Varahamihira gives four chapters to rain, because "as food is the support of life, and food depends upon rain, it is important to discover the laws of rain by any means" (Brihat Samhita 21.1).

• The "pregnancy" of clouds (garbha, chapter 21): the clouds, winds and temperatures in the months before the monsoon are watched; a "conception" of rain is said to be "delivered" about 195 days later. This is a traditional long-range forecasting method based on observation.
• Measuring rain (chapter 23): "Falling rain should be collected in a vessel with a circular mouth, a cubit in diameter, and the collected rain should be measured with a vessel whose capacity is an adhaka" (23.2). This is a rain gauge — an instrument for quantitative measurement, described in the sixth century.
• Rohini yoga (chapter 24) and Ashadhi yoga (26): the Moon's conjunction with Rohini and the Ashadhas, and the winds at those times, are used to forecast the season's rain.
• The winds (27) and signs of immediate rain (28).

#Water underground

The chapter on "under-currents" (dakargala, Brihat Samhita 54) explains how to find groundwater for wells: "Just in the same way as there are arteries for the circulation of blood in human bodies, there are water courses running in all directions above and below within the Earth" (54.1). It notes that rainwater "is of one color and one flavor; after contact with the Earth, both the color and the flavor vary with those of the ground through which it flows. This will be found to be the case on actual examination" (54.2). It then gives signs — particular trees, termite mounds, soils and rocks — that indicate water at a given depth.

#Omens and portents

Many chapters deal with omens (shakuna): the cries and movements of birds and animals, especially the crow (chapters 86–96 in the continuous numbering), and portents (utpata, chapter 46) — unusual events in the sky, on earth or among living things, read as signs for the kingdom. The chapter on Angavidya (51) teaches the reading of a questioner's gestures (Chapter 40).

The omen chapters are of great historical interest — they show how people read their world — but they are not predictions in any testable sense, and this course does not use them.

#Kingdoms, prices and the year

The planetary chapters (Brihat Samhita 3–20) describe what the Sun, Moon and each planet portend for countries, kings, crops and prices according to their appearance, motion and position. Chapter 8 describes Jupiter's sixty-year cycle (samvatsara), which still names the years in Indian calendars (Chapter 5). Chapter 14, "the division of the tortoise" (kurma vibhaga), assigns the regions of India to the nakshatras — a sixth-century map of the subcontinent. Chapters 41–42 forecast the prices of commodities from the planets.

This is mundane astrology: astrology of nations, kings, weather and markets, rather than of persons.

#The practical arts

A large part of the Brihat Samhita has nothing to do with the sky:

• architecture (vastu): house-building (53) and temples (56);
• gardening and trees (55);
• cements (57) and images of the gods (58);
• the signs of good animals, swords and gems — diamonds, pearls, rubies, emeralds (80–83);
• perfumes (77).

These chapters are a record of applied knowledge, and they explain why jyotisha in the old sense was a broader science than horoscopy.

#How to read mundane prediction today

Mundane predictions — of wars, epidemics, famines, market crashes and the fall of governments — are among the most dangerous uses of astrology:

• they can spread fear to large numbers of people at once;
• they are usually vague enough to be "confirmed" by something;
• they can be used to sell remedies or rituals on a large scale.

This course reads the Brihat Samhita's mundane chapters as history of ideas: a record of what was observed, believed and feared, and of how a great scholar organised it. Its observational methods — the rain gauge, the study of winds and clouds, the indicators of groundwater — can be compared with modern measurement, and such comparisons are interesting and worth doing openly. Its predictions for kingdoms are not forecasts, and should not be presented as such.

#Summary

• Samhita is the third branch of Jyotisha: omens, weather, mundane matters and practical arts; its great book is Varahamihira's Brihat Samhita.
• Varahamihira explains eclipses by the Earth's shadow and the Moon's disc, and says that Rahu does not cause them (Brihat Samhita 5.8–13).
• He describes a rain gauge (23.2), long-range rain forecasting from the "pregnancy" of clouds (21), and indicators of groundwater (54).
• The omen, portent and mundane chapters are of historical value; the course reads them as history, not forecast.
• The Brihat Samhita also covers architecture, gardening, images, gems and animals — a record of applied knowledge.

#Exercises

1. What are the three branches of Jyotisha, and to which does the Brihat Samhita mainly belong?
2. What does Varahamihira say causes a lunar eclipse? A solar eclipse?
3. Describe Varahamihira's rain gauge.
4. Why is mundane prediction especially open to misuse?
5. Choose one practical chapter of the Brihat Samhita (for example on groundwater or building) and say how its claims could be checked today.

Answers: 1. Ganita (astronomy), hora (horoscopy) and samhita (omens, weather, mundane matters, practical arts); the Brihat Samhita is the classic of samhita. 2. The Moon entering the Earth's shadow; the Moon covering the Sun's disc (5.8). 3. A vessel with a circular mouth a cubit across collects the rain, which is then measured with a standard vessel of one adhaka (23.2). 4. Because it can frighten many people at once, is usually vague enough to be "confirmed", and can be used to sell remedies widely. 5. For example: record the indicators the chapter names (trees, soil, termite mounds) at sites where wells are dug, and compare them with the depth at which water is actually found.