Ben Dykes in his translation of Abu Ma’Shar on the Revolutions of the Years of Nativities (2019) discusses the concept of “lord of the orb.” Dr. Dykes notes that it appears unclear, in the text which he translated, exactly how the lords of the orb are to be distributed over the course of the solar revolutions during the native’s lifetime. Dykes presents a “continuous loop” version and a “single cycle” version of lords of the orb on pages 126 and 128 respectively.
I came across the use of lord of the orb while reading a 15th century manuscript by Diego de Torres, an astrology professor of the University of Salamanca, Spain. Torres’s 15th century text reveals how the lord of the orb was understood at the time. Here is the original text, handwritten in Old Castilian Spanish, which makes use of what Dr. Dykes calls the “continuous loop” version of the planetary hour lords of the orb:

Here is a transcription of the above text with my translation of Diego de Torres’s words from 15th century Spanish into English (if any Spanish scholars see an error in my translation, please leave a comment and I will correct it):
Capitulo 6º: que declara el señor del orbe, o del circulo o de la hora, que es vna mesma cosa.
Chapter 6: what the lord of the orb (or of the circle, or of the hour, which all refer to the same thing) declares.
Es de notar que el señor de la hora del tiempo de la natiuidad se dize el señor del orbe para el primer anno de la natiuidad y por aquel has tu de jusgar de la vida y de la disposition en costumbres, sanidad y enfermedad del nascido y de los otros significados de la primera casa en el primer anno.
It should be noted that the lord of the hour of the time of birth is called the “lord of the orb” for the first year of life and by it one shall judge the life and disposition of the native with regard to habits, health and illnesses and other significations of the 1st house during the 1st year of life,
en el 2º anno de la Natiuidad el señor del orbe o del circulo sera el señor de la hora, 2º començando desde el tiempo de la natiuidad y aquel se dize el señor de la hora de la casa 2ª, del qual has tu de tomar los juysyos en el 2º anno de la natiuidad y jusgar de las substancias y Riquezas que vernan al nascido. Segund el estado que touiere en fortaleza y fortunio o infortunio.
during the 2nd year of life the lord of the orb, or of the circle, will be the lord of the 2nd hour following the birth time of the native and it is called the “lord of the hour of the 2nd house” from which one may make judgements regarding the 2nd year of life and about the substance and riches which will come to the native — according to the condition [of the lord of the orb] whether it be fortified, and fortunate or unfortunate.
y en el 3º anno seruira el señor de la hora tercera para las cosas de la casa 3ª y segund su estado sera su juysio y ansy hemos de desyr de los otros señores de las horas para el
anno 4º, 5º y 6º y otros;
and in the 3rd year [of life] the lord of the 3rd hour [after birth] will serve for matters of the 3rd house [and 3rd year of life] and, according to its condition, you will make your judgement; and similarly we may regard the other lords of the hours for the 4th, 5th and 6th years of life, and so on;
de manera que pasados 12 annos al 13º bolvamos al primero y es aqui de notar que estos señores se han de tomar por la diuision de las horas, diuidiendo cada vn dia, agora grande o pequeño, en 12 partes yguales; y eso mesmo la noche, y ver entonçes los planetas que Reynan por las horas, y para que mejor esto se entienda, para obrar en las Reuoluciones, hyse aqui vna tablilla.
so that having passed through 12 years, in the 13th year we return to the 1st house; and it should be noted that these lords [of the orb] are taken from the division of hours, which partitions a day, however long or short, into 12 equal parts; and the same is done for the night, and then see which planets rule each of the hours; and to make sure that you understand this [sequence of lords of the orb] and can make use of it in the revolutions [of years], I have prepared the following table.

Unfortunately, Diego de Torres did not have access to an Excel spreadsheet in the 15th century, and he made a calculation error in the third column of his table. I have corrected his error and will present his table in modern format. The numbers in this table refer to the year of life, for example, “1” refers to the year from age 0 to age 1 so that the native is age 1 at the completion of the yearly cycle, “2” to the year from age 1 to age 2 so that the native is age 2 at the completion of the yearly cycle, and so on. You can see from the table that Venus is lord of the orb in years 1, 8, 15, 22, 29, and 36 during the first 42 years of this person’s life.
In this table columns 1, 2 and 3 refer to the annual revolution up to age 42, for the case in which Venus is Lord of the Orb during the 1st annual revolution, starting at birth. I believe that Diego de Torres was thinking of ordinal rather than cardinal numbers when he constructed this table. He uses the phrase “conpliste revolución” to head the column for “lord of the orb,” meaning that the planet listed was the lord for the year indicated: 1 for the 1st year of life, 2 for the 2nd year of life, etc. If the first year of life has Venus as the planetary hour of the nativity and is thus lord of the orb at birth, this table shows the lords of the orb in sequence for each year from birth onward.
The same method would be followed to construct a table for a planet other than Venus as lord of the orb. Ben Dykes refers to this distribution of lords of the orb as the “continuous loop” version, which appears to be how astrologers in the 15th century understood this technique.
To make the above clearer, let me state it a little differently. The lord of the orb at birth is the planetary hour at the time of birth. The sequence then goes in the Chaldean order from slowest to fastest planet: Saturn – Jupiter – Mars – Sun – Venus – Mercury – Moon, and repeats every 7 years. So you have the same lord of the orb at birth and at ages 7, 14, 21, 28, 35, 42, 49, 56, 63, 70, 77, and so on. For example, Donald Trump was born during a Jupiter hour, so his lord of the orb at age 70, when he won the presidency, was also Jupiter.
Basically, you take the planetary hour at birth and assign it to the first house and to the first year of life, the 2nd planetary hour after birth to the 2nd house and the 2nd year of life, and your do this indefinitely. The lord of the orb appears to act like a participating ruler which works with the profected Asc ruler and the natal house rulers to help delineate the chart. Its condition in the Solar Return as well as in the nativity indicate how matters related to its house will go that year.
Addendum (4 Jan 2021): Lord of the Orb in the 16th century work of Giuntini
Margherita Fiorello pointed out that Francesco Giuntini (Junctinis or Junctinus) discussed the lord of the orb along with profections in his 16th century text on astrology. Here are some tables from Giuntini’s book, which I reproduced from a Google Books digitized version online.


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All original material in this post is copyright Anthony Louis 2021.
This is amazing and very interesting Dr. Louis, thank you for discovering and sharing.
Thanks, Raul, for the kind words. Much appreciated.
I really appreciate the time and research that you do, it is very interesting to find out more about the origins of various methods used during the centuries regarding astrology.