Mishnah 4 in the eighth chapter of Maseches Menachos deals with harvesting olives and producing olive oil. The mishnah is packed with terms and details, so let us first set out the general picture from the outside, and only afterward examine the language of the mishnah itself.
The olive harvest is divided into three stages, according to where the olives are located on the tree:
The olives at the top of the tree.
The olives in the middle of the tree.
The olives at the bottom of the tree.
In each of the three stages, three grades of oil are produced. The oil does not come out of the olive on its own, but through crushing, pressing or grinding; and the more force applied to the olive, the more oil is obtained - but also more waste and sediment that mix into the oil.
The three grades of oil are:
First grade: crushing alone, with a mortar and pestle, so that the oil can come out without the olive being pressed or ground. This is the most refined and clearest oil.
Second grade: pressing under pressure.
Third grade: grinding, followed by pressing again, to extract the very last drop.
Let us examine the language of the mishnah:
"Sheloshah zeisim" - three stages in the olive harvest. "U'vahen sheloshah sheloshah shemanim" - each of the three stages produces three grades of olive oil.
The first olive - the olives at the top of the tree:
"Hazayis harishon - megargero b'rosh hazayis" - 'megargero' means picking. One picks the uppermost olives at the top of the tree, upon which the sun shines directly, and which are therefore the ripest and finest. "V'chosesh v'nosen l'soch hasal" - one crushes them in a mortar and places them in a wicker basket that has small holes at its bottom, which serves as a strainer: the pieces of olive and the dregs are held back in the basket, while the oil drips down on its own into the receiving vessel beneath it. This is the clear, virgin olive oil.
"Rabbi Yehudah omer: sevivos hasal" - in his view one does not place the crushed olives at the bottom of the basket, but rather arranges them around its walls, so that the oil flows down along the wall. This flow lengthens the filtering time, and additional waste is caught along the way, so that the oil dripping out below is purer. "Zeh rishon" - this is the first grade of the first stage.
"Ta'an b'korah" - one presses the olives with the beam press. The beam of the press is an extremely long wooden beam that serves as an enormous lever arm and presses on the olives with great force in order to extract additional oil from them. "Rabbi Yehudah omer: ba'avanim" - in his view one may not use the beam press, since its pressure is too great and a great deal of waste mixes into the oil; rather, one places stones on the olives, which press them with more moderate pressure, and consequently less sediment and waste mix into the oil. "Zeh sheni" - this is the second grade of the first stage.
"Chazar v'tachan v'ta'an" - one returns to the crushed olives and grinds them into a kind of paste. The grinding is done in an olive mill: a wide basin in which a heavy round stone rolls, turned by an animal harnessed to a beam. The olives are placed in the basin and ground into a paste, the paste is gathered into sacks, and the sacks are placed under the press to be pressed again with full force. Understandably, a good deal of sediment mixes into this oil, but in this way every last drop is extracted from it. "Zeh shlishi" - this is the third grade of oil produced from the first stage.
"HaRishon lamenorah" - the first grade of oil is fit for kindling the Menorah, for it says of it "shemen zayis zach kasis lama'or": clear, pure oil is required, and therefore one may not use oil that came out through heavy pressing or through grinding. "V'hash'ar lamenachos" - the second and third grades of oil are fit for the menachos. Strictly speaking, it would have been fitting to use only the pure beaten oil, but it is expensive, and the Holy One, Blessed is He, has compassion for the money of Israel, and therefore the lower grades too are fit for a minchah.
The second olive - the olives at the height of the roof:
"HaSheini - m'gargero b'rosh hagag" - these are the olives in the middle of the tree, at the height of the roof. The Bartenura explains, as do the other commentators, that they would plant their olive trees close to their houses, so that there was convenient access to the tree from the roof. These olives too ripened in direct sunlight, but less light reached them, and therefore they are less ripe and the quality of their oil is inferior.
"V'chosesh v'nosein l'soch hasal" - one crushes them in a mortar and places them in a basket that serves as a strainer, and what drips out below is collected in a vessel; this is the first grade of oil of the second stage. "Rabbi Yehudah omer: s'vivos hasal" - following his opinion above, that the olives should be arranged around the walls of the basket, so that the oil will flow down along them and be filtered better. "Zeh rishon".
"Ta'an bakorah" - one presses them in the beam press. "Rabbi Yehudah omer: ba'avanim" - following his opinion above: stones alone, less pressure and less sediment. "Zeh sheini". "Chazar v'tachan v'ta'an, zeh shlishi" - one returns to the olives that have already been pressed, grinds them and presses them again in the beam press - according to all opinions - until nothing is left.
"HaRishon lamenorah v'hash'ar lamenachos" - the first grade of oil of this stage is fit for the Menorah as well, since it is still "shemen zayis zach kasis", clear oil; while the second and third grades are fit for the menachos.
The third olive - the olives at the bottom of the tree:
"HaShlishi - otno b'soch habayis ad sheyilkeh" - these are the olives that never ripen fully on the tree. They are gathered together in a ma'atan, a kind of vat, and left to sit there until they begin to ferment and soften. This process is what enables them to release their oil. But as they soften they give off a foul liquid, whose smell and taste are unpleasant. "U'ma'alehu u'menagvo b'rosh hagag" - after they have sat in the ma'atan long enough, they are brought up to the roof and dried in the sun, in order to remove the foul liquid that came out of them, so that the resulting oil should not be malodorous.
"V'chosesh v'nosein l'soch hasal" - crushing in a mortar and placing in a basket, to obtain the first grade of the third stage. "Rabbi Yehudah omer: s'vivos hasal" - around the walls of the basket, for finer filtering. "Zeh rishon". "Ta'an bakorah" - pressing in the olive press with the beam; "Rabbi Yehudah omer: ba'avanim" - not with the beam, whose pressure is great, but with stones. "Zeh sheini". "Chazar v'tachan v'ta'an, zeh shlishi" - one grinds them and returns them to the press, down to the last drop. "HaRishon lamenorah" - the first grade is fit for the Menorah, for it too is clear beaten olive oil; "v'hash'ar lamenachos" - the second and third grades are fit for the menachos.
In summary: our Mishnah teaches that any oil that was not pressed with force and was not ground and pressed is fit for the Menorah, since it is clear olive oil; but there are three levels of preference among them: ideally from the first stage, the olives at the top of the tree; and if not - from the second stage; and if not - from the third stage.
We thus have nine categories in all: three stages of harvesting, and in each of them three grades of oil. In the next Mishnah we will deal with the hierarchy among them regarding the preparation of the menachos, since all nine are fit for a minchah, at least after the fact.