Chapter IX

used before a singular noun to mean one of a group, when it is not a particular one

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

any specific behavior

From this reading All the three were in the stationary period of life, and, consequently, in the possession of full bodily strength and activity.

(quantifier) used with either mass or count nouns to indicate the whole number or amount of or every one of a class

From this reading All the three were in the stationary period of life, and, consequently, in the possession of full bodily strength and activity.

used to join words or parts of a sentence that go together

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

at the same time that; because; in the way that

From this reading Still, to venture on a climb through a dense mist, on the face of a nearly precipitous and wholly unknown mountain, where a single slip would be certainly followed by immediate destruction, was regarded by their comrades as too hazardous to be thought of.

relating or belonging to the science of astronomy

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

used with a past participle to form the passive, or with -ing for continuous tenses

From this reading Still, to venture on a climb through a dense mist, on the face of a nearly precipitous and wholly unknown mountain, where a single slip would be certainly followed by immediate destruction, was regarded by their comrades as too hazardous to be thought of.

in bodily form

From this reading All the three were in the stationary period of life, and, consequently, in the possession of full bodily strength and activity.

the two together, not just one

From this reading The cliff was in most places rough enough to give good hold for both hands and feet.

showing who or what does the action

From this reading The levelling of the rock was necessarily a work which required a good deal of time; and, while it was proceeding, three of the engineers formed the daring project of scrambling up the cliff, into the cloud, and endeavouring to penetrate through it by themselves.

definitely or positively (“sure” is sometimes used informally for “surely”)

From this reading Still, to venture on a climb through a dense mist, on the face of a nearly precipitous and wholly unknown mountain, where a single slip would be certainly followed by immediate destruction, was regarded by their comrades as too hazardous to be thought of.

a steep high face of rock

From this reading The levelling of the rock was necessarily a work which required a good deal of time; and, while it was proceeding, three of the engineers formed the daring project of scrambling up the cliff, into the cloud, and endeavouring to penetrate through it by themselves.

go upward with gradual or continuous progress

From this reading Still, to venture on a climb through a dense mist, on the face of a nearly precipitous and wholly unknown mountain, where a single slip would be certainly followed by immediate destruction, was regarded by their comrades as too hazardous to be thought of.

make overcast or cloudy

From this reading The levelling of the rock was necessarily a work which required a good deal of time; and, while it was proceeding, three of the engineers formed the daring project of scrambling up the cliff, into the cloud, and endeavouring to penetrate through it by themselves.

plural of “comrade” — a friend who is frequently in the company of another

From this reading Still, to venture on a climb through a dense mist, on the face of a nearly precipitous and wholly unknown mountain, where a single slip would be certainly followed by immediate destruction, was regarded by their comrades as too hazardous to be thought of.

(sentence connectors) because of the reason given

From this reading All the three were in the stationary period of life, and, consequently, in the possession of full bodily strength and activity.

the act of constructing something

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

a quality of spirit that enables you to face danger or pain without showing fear

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

a challenge to do something dangerous or foolhardy

From this reading The levelling of the rock was necessarily a work which required a good deal of time; and, while it was proceeding, three of the engineers formed the daring project of scrambling up the cliff, into the cloud, and endeavouring to penetrate through it by themselves.

act on verbally or in some form of artistic expression

From this reading The levelling of the rock was necessarily a work which required a good deal of time; and, while it was proceeding, three of the engineers formed the daring project of scrambling up the cliff, into the cloud, and endeavouring to penetrate through it by themselves.

permitting little if any light to pass through because of denseness of matter

From this reading Still, to venture on a climb through a dense mist, on the face of a nearly precipitous and wholly unknown mountain, where a single slip would be certainly followed by immediate destruction, was regarded by their comrades as too hazardous to be thought of.

the termination of something by causing so much damage to it that it cannot be repaired or no longer exists

From this reading Still, to venture on a climb through a dense mist, on the face of a nearly precipitous and wholly unknown mountain, where a single slip would be certainly followed by immediate destruction, was regarded by their comrades as too hazardous to be thought of.

discovered or determined by scientific observation

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

something with a round shape resembling a flat circular plate

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

Dictionary entry pending editorial verification. Tap Listen to hear the word.

From this reading The levelling of the rock was necessarily a work which required a good deal of time; and, while it was proceeding, three of the engineers formed the daring project of scrambling up the cliff, into the cloud, and endeavouring to penetrate through it by themselves.

plural of “engineer” — a person who uses scientific knowledge to solve practical problems

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

an adequate quantity; a quantity that is large enough to achieve a purpose

From this reading The cliff was in most places rough enough to give good hold for both hands and feet.

the front of the human head from the forehead to the chin and ear to ear

From this reading Still, to venture on a climb through a dense mist, on the face of a nearly precipitous and wholly unknown mountain, where a single slip would be certainly followed by immediate destruction, was regarded by their comrades as too hazardous to be thought of.

plural of “foot” — the part of the leg of a human being below the ankle joint

From this reading The cliff was in most places rough enough to give good hold for both hands and feet.

start firing a weapon

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

past form of “follow” — to travel behind, go after, come after

From this reading Still, to venture on a climb through a dense mist, on the face of a nearly precipitous and wholly unknown mountain, where a single slip would be certainly followed by immediate destruction, was regarded by their comrades as too hazardous to be thought of.

intended to be given to, or used by, somebody

From this reading The cliff was in most places rough enough to give good hold for both hands and feet.

having or given a form or shape

From this reading The levelling of the rock was necessarily a work which required a good deal of time; and, while it was proceeding, three of the engineers formed the daring project of scrambling up the cliff, into the cloud, and endeavouring to penetrate through it by themselves.

containing as much or as many as is possible or normal

From this reading All the three were in the stationary period of life, and, consequently, in the possession of full bodily strength and activity.

to or at a greater extent or degree or a more advanced stage (“further” is used more often than “farther” in this abstract sense)

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

cause to have, in the abstract sense or physical sense

From this reading The cliff was in most places rough enough to give good hold for both hands and feet.

having desirable or positive qualities especially those suitable for a thing specified

From this reading The levelling of the rock was necessarily a work which required a good deal of time; and, while it was proceeding, three of the engineers formed the daring project of scrambling up the cliff, into the cloud, and endeavouring to penetrate through it by themselves.

relatively large in size or number or extent; larger than others of its kind

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

(biology) the process of an individual organism growing organically; a purely biological unfolding of events involved in an organism changing gradually from a simple to a more complex level

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

(with “in”) guardianship over; in divorce cases it is the right to house and care for and discipline a child

From this reading The cliff was in most places rough enough to give good hold for both hands and feet.

involving risk or danger

From this reading Still, to venture on a climb through a dense mist, on the face of a nearly precipitous and wholly unknown mountain, where a single slip would be certainly followed by immediate destruction, was regarded by their comrades as too hazardous to be thought of.

any place of complete bliss and delight and peace

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

cause to continue in a certain state, position, or activity; e.g., “keep clean”

From this reading The cliff was in most places rough enough to give good hold for both hands and feet.

a person who invites guests to a social event (such as a party in his or her own home) and who is responsible for them while they are there

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

Dictionary entry pending editorial verification. Tap Listen to hear the word.

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

of the present time and place

From this reading Still, to venture on a climb through a dense mist, on the face of a nearly precipitous and wholly unknown mountain, where a single slip would be certainly followed by immediate destruction, was regarded by their comrades as too hazardous to be thought of.

inside something, or within a place, period, or state

From this reading All the three were in the stationary period of life, and, consequently, in the possession of full bodily strength and activity.

moving to the inside of something

From this reading The levelling of the rock was necessarily a work which required a good deal of time; and, while it was proceeding, three of the engineers formed the daring project of scrambling up the cliff, into the cloud, and endeavouring to penetrate through it by themselves.

a thing, animal, or idea already mentioned

From this reading The levelling of the rock was necessarily a work which required a good deal of time; and, while it was proceeding, three of the engineers formed the daring project of scrambling up the cliff, into the cloud, and endeavouring to penetrate through it by themselves.

the psychological result of perception and learning and reasoning

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

Dictionary entry pending editorial verification. Tap Listen to hear the word.

From this reading The levelling of the rock was necessarily a work which required a good deal of time; and, while it was proceeding, three of the engineers formed the daring project of scrambling up the cliff, into the cloud, and endeavouring to penetrate through it by themselves.

a characteristic state or mode of living

From this reading All the three were in the stationary period of life, and, consequently, in the possession of full bodily strength and activity.

become covered with mist

From this reading Still, to venture on a climb through a dense mist, on the face of a nearly precipitous and wholly unknown mountain, where a single slip would be certainly followed by immediate destruction, was regarded by their comrades as too hazardous to be thought of.

used to form the superlative

From this reading The cliff was in most places rough enough to give good hold for both hands and feet.

a land mass that projects well above its surroundings; higher than a hill

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

(of actions or states) slightly short of or not quite accomplished; all but

From this reading Still, to venture on a climb through a dense mist, on the face of a nearly precipitous and wholly unknown mountain, where a single slip would be certainly followed by immediate destruction, was regarded by their comrades as too hazardous to be thought of.

in an essential manner

From this reading The levelling of the rock was necessarily a work which required a good deal of time; and, while it was proceeding, three of the engineers formed the daring project of scrambling up the cliff, into the cloud, and endeavouring to penetrate through it by themselves.

information about recent and important events

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

a building designed and equipped to observe astronomical phenomena

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

belonging to, or connected with, somebody or something

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

touching and supported by a surface

From this reading Still, to venture on a climb through a dense mist, on the face of a nearly precipitous and wholly unknown mountain, where a single slip would be certainly followed by immediate destruction, was regarded by their comrades as too hazardous to be thought of.

past form of “pass” — go across or through

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

pass into or through, often by overcoming resistance

From this reading The levelling of the rock was necessarily a work which required a good deal of time; and, while it was proceeding, three of the engineers formed the daring project of scrambling up the cliff, into the cloud, and endeavouring to penetrate through it by themselves.

an amount of time

From this reading All the three were in the stationary period of life, and, consequently, in the possession of full bodily strength and activity.

plural of “place” — a point located with respect to surface features of some region

From this reading The cliff was in most places rough enough to give good hold for both hands and feet.

the act of having and controlling property

From this reading All the three were in the stationary period of life, and, consequently, in the possession of full bodily strength and activity.

done with very great haste and without due deliberation

From this reading Still, to venture on a climb through a dense mist, on the face of a nearly precipitous and wholly unknown mountain, where a single slip would be certainly followed by immediate destruction, was regarded by their comrades as too hazardous to be thought of.

(law) the institution of a sequence of steps by which legal judgments are invoked

From this reading The levelling of the rock was necessarily a work which required a good deal of time; and, while it was proceeding, three of the engineers formed the daring project of scrambling up the cliff, into the cloud, and endeavouring to penetrate through it by themselves.

communicate vividly

From this reading The levelling of the rock was necessarily a work which required a good deal of time; and, while it was proceeding, three of the engineers formed the daring project of scrambling up the cliff, into the cloud, and endeavouring to penetrate through it by themselves.

done or occurring in a brief period of time

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

the manner in which something is greeted

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

past form of “regard” — deem to be

From this reading Still, to venture on a climb through a dense mist, on the face of a nearly precipitous and wholly unknown mountain, where a single slip would be certainly followed by immediate destruction, was regarded by their comrades as too hazardous to be thought of.

necessary for relief or supply

From this reading The levelling of the rock was necessarily a work which required a good deal of time; and, while it was proceeding, three of the engineers formed the daring project of scrambling up the cliff, into the cloud, and endeavouring to penetrate through it by themselves.

a lump or mass of hard consolidated mineral matter

From this reading The levelling of the rock was necessarily a work which required a good deal of time; and, while it was proceeding, three of the engineers formed the daring project of scrambling up the cliff, into the cloud, and endeavouring to penetrate through it by themselves.

having or caused by an irregular surface

From this reading The cliff was in most places rough enough to give good hold for both hands and feet.

cut with a saw

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

-ing form of “scramble” — to move hurriedly

From this reading The levelling of the rock was necessarily a work which required a good deal of time; and, while it was proceeding, three of the engineers formed the daring project of scrambling up the cliff, into the cloud, and endeavouring to penetrate through it by themselves.

a white or silvered surface where pictures can be projected for viewing

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

being or characteristic of a single thing or person

From this reading Still, to venture on a climb through a dense mist, on the face of a nearly precipitous and wholly unknown mountain, where a single slip would be certainly followed by immediate destruction, was regarded by their comrades as too hazardous to be thought of.

move stealthily

From this reading Still, to venture on a climb through a dense mist, on the face of a nearly precipitous and wholly unknown mountain, where a single slip would be certainly followed by immediate destruction, was regarded by their comrades as too hazardous to be thought of.

standing still

From this reading All the three were in the stationary period of life, and, consequently, in the possession of full bodily strength and activity.

not in physical motion

From this reading Still, to venture on a climb through a dense mist, on the face of a nearly precipitous and wholly unknown mountain, where a single slip would be certainly followed by immediate destruction, was regarded by their comrades as too hazardous to be thought of.

the property of being physically or mentally strong

From this reading All the three were in the stationary period of life, and, consequently, in the possession of full bodily strength and activity.

used before a noun that is already known, already mentioned, or the only one of its kind

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

belonging to the people or things already mentioned

From this reading Still, to venture on a climb through a dense mist, on the face of a nearly precipitous and wholly unknown mountain, where a single slip would be certainly followed by immediate destruction, was regarded by their comrades as too hazardous to be thought of.

used when the people doing the action are also its object

From this reading The levelling of the rock was necessarily a work which required a good deal of time; and, while it was proceeding, three of the engineers formed the daring project of scrambling up the cliff, into the cloud, and endeavouring to penetrate through it by themselves.

the people, animals, or things already mentioned, as the subject

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

the content of cognition; the main thing you are thinking about

From this reading Still, to venture on a climb through a dense mist, on the face of a nearly precipitous and wholly unknown mountain, where a single slip would be certainly followed by immediate destruction, was regarded by their comrades as too hazardous to be thought of.

the cardinal number that is the sum of one and one and one

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

from one end or side of something to the other

From this reading The levelling of the rock was necessarily a work which required a good deal of time; and, while it was proceeding, three of the engineers formed the daring project of scrambling up the cliff, into the cloud, and endeavouring to penetrate through it by themselves.

in every part of a place, or for the whole of a period

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

an instance or single occasion for some event

From this reading The levelling of the rock was necessarily a work which required a good deal of time; and, while it was proceeding, three of the engineers formed the daring project of scrambling up the cliff, into the cloud, and endeavouring to penetrate through it by themselves.

used before the base form of a verb to make the infinitive

From this reading The levelling of the rock was necessarily a work which required a good deal of time; and, while it was proceeding, three of the engineers formed the daring project of scrambling up the cliff, into the cloud, and endeavouring to penetrate through it by themselves.

to a degree exceeding normal or proper limits

From this reading Still, to venture on a climb through a dense mist, on the face of a nearly precipitous and wholly unknown mountain, where a single slip would be certainly followed by immediate destruction, was regarded by their comrades as too hazardous to be thought of.

not known

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

being or moving higher in position or greater in some value; being above a former position or level

From this reading The levelling of the rock was necessarily a work which required a good deal of time; and, while it was proceeding, three of the engineers formed the daring project of scrambling up the cliff, into the cloud, and endeavouring to penetrate through it by themselves.

any venturesome undertaking especially one with an uncertain outcome

From this reading Still, to venture on a climb through a dense mist, on the face of a nearly precipitous and wholly unknown mountain, where a single slip would be certainly followed by immediate destruction, was regarded by their comrades as too hazardous to be thought of.

the past form of “be” used with I, he, she, it, or a singular noun

From this reading The levelling of the rock was necessarily a work which required a good deal of time; and, while it was proceeding, three of the engineers formed the daring project of scrambling up the cliff, into the cloud, and endeavouring to penetrate through it by themselves.

the past form of “be” used with you, we, they, or a plural noun

From this reading All the three were in the stationary period of life, and, consequently, in the possession of full bodily strength and activity.

in or at the place that

From this reading Still, to venture on a climb through a dense mist, on the face of a nearly precipitous and wholly unknown mountain, where a single slip would be certainly followed by immediate destruction, was regarded by their comrades as too hazardous to be thought of.

used to introduce a clause giving more about a thing just mentioned

From this reading The levelling of the rock was necessarily a work which required a good deal of time; and, while it was proceeding, three of the engineers formed the daring project of scrambling up the cliff, into the cloud, and endeavouring to penetrate through it by themselves.

during the time that

From this reading The levelling of the rock was necessarily a work which required a good deal of time; and, while it was proceeding, three of the engineers formed the daring project of scrambling up the cliff, into the cloud, and endeavouring to penetrate through it by themselves.

to a complete degree or to the full or entire extent (“whole” is often used informally for “wholly”)

From this reading Still, to venture on a climb through a dense mist, on the face of a nearly precipitous and wholly unknown mountain, where a single slip would be certainly followed by immediate destruction, was regarded by their comrades as too hazardous to be thought of.

exert oneself by doing mental or physical work for a purpose or out of necessity

From this reading The levelling of the rock was necessarily a work which required a good deal of time; and, while it was proceeding, three of the engineers formed the daring project of scrambling up the cliff, into the cloud, and endeavouring to penetrate through it by themselves.

everything that exists anywhere

From this reading Of the great courage of three engineers—How they passed the Screen and saw the Host of Heaven—How they further discovered a Disk of Unknown Fire—Of the reception of the news throughout the world—Of the construction of a mountain Observatory; and of the rapid growth of Astronomical knowledge.

used for something imagined, polite, or habitual in the past

From this reading Still, to venture on a climb through a dense mist, on the face of a nearly precipitous and wholly unknown mountain, where a single slip would be certainly followed by immediate destruction, was regarded by their comrades as too hazardous to be thought of.