The Reminiscences of an Astronomer

by Simon Newcomb

To our astonishment the Astronomer Royal at once took up the thread:—

"'And as they passed by the great house of a lord,
A beautiful chariot there came,
To take some most elegant ladies abroad,
Who straightway got into the same,'"

and went on to the end. I do not know which of the two was more surprised: Airy, to find an American woman who was interested in his favorite ballad, or she to find that he could repeat it by heart. The incident was the commencement of a family friendship which has outlived both the heads of the Airy family.

We may look back on Airy as the most commanding figure in the astronomy of our time. He owes this position not only to his early works in mathematical astronomy, but also to his ability as an organizer. Before his time the working force of an observatory generally consisted of individual observers, each of whom worked to a greater or less extent in his own way. It is true that organization was not unknown in such institutions. Nominally, at least, the assistants in a national observatory were supposed to follow the instructions of a directing head. This was especially the case at Greenwich. Still, great dependence was placed upon the judgment and ability of the observer himself, who was generally expected to be a man well trained in his specialty, and able to carry on good work without much help. From Airy's point of view, it was seen that a large part of the work necessary to the attainment of the traditional end of the Royal Observatory was of a kind that almost any bright schoolboy could learn to do in a few weeks, and that in most of the remaining part plodding industry, properly directed, was more important than scientific training. He could himself work out all the mathematical formulæ and write all the instructions required to keep a small army of observers and computers employed, and could then train in his methods a few able lieutenants, who would see that all the details were properly executed. Under these lieutenants was a grade comprising men of sufficient technical education to enable them to learn how to point the telescope, record a transit, and perform the other technical operations necessary in an astronomical observation. A third grade was that of computers: ingenious youth, quick at figures, ready to work for a compensation which an American laborer would despise, yet well enough schooled to make simple calculations. Under the new system they needed to understand only the four rules of arithmetic; indeed, so far as possible Airy arranged his calculations in such a way that subtraction and division were rarely required. His boys had little more to do than add and multiply. Thus, so far as the doing of work was concerned, he introduced the same sort of improvement that our times have witnessed in great manufacturing establishments, where labor is so organized that unskilled men bring about results that formerly demanded a high grade of technical ability. He introduced production on a large scale into astronomy.

At the time of my visit, it was much the fashion among astronomers elsewhere to speak slightingly of the Greenwich system. The objections to it were, in substance, the same that have been made to the minute subdivision of labor. The intellect of the individual was stunted for the benefit of the work. The astronomer became a mere operative. Yet it must be admitted that the astronomical work done at Greenwich during the sixty years since Airy introduced his system has a value and an importance in its specialty that none done elsewhere can exceed. All future conclusions as to the laws of motion of the heavenly bodies must depend largely upon it.

The organization of his little army necessarily involved a corresponding change in the instruments they were to use. Before his time the trained astronomer worked with instruments of very delicate construction, so that skill in handling them was one of the requisites of an observer. Airy made them in the likeness of heavy machinery, which could suffer no injury from a blow of the head of a careless observer. Strong and simple, they rarely got out of order. It is said that an assistant who showed a visiting astronomer the transit circle some times hit it a good slap to show how solid it was; but this was not done on the present occasion. The little army had its weekly marching orders and made daily reports of progress to its commander, who was thus enabled to control the minutest detail of every movement.

In the course of the evening Airy gave me a lesson in method, which was equally instructive and entertaining. In order to determine the longitude of Gibraltar, it was necessary that time signals should be sent by telegraph from the Royal Observatory. Our conversation naturally led us into a discussion of the general subject of such operations. I told him of the difficulties we had experienced in determining a telegraphic longitude,—that of the Harvard Observatory from Washington, for example,—because it was only after a great deal of talking and arranging on the evening of the observation that the various telegraph stations between the two points could have their connections successfully made at the same moment. At the appointed hour the Washington operator would be talking with the others, to know if they were ready, and so a general discussion about the arrangements might go on for half an hour before the connections were all reported good. If we had such trouble in a land line, how should we get a connection from London to the Gibraltar cable through lines in constant use?

"But," said Airy, "I never allow an operator who can speak with the instruments to take part in determining a telegraphic longitude."

"Then how can you get the connections all made from one end of the line to the other, at the same moment, if your operators cannot talk to one another?"

"Nothing is simpler. I fix in advance a moment, say eight o'clock Greenwich mean time, at which signals are to commence. Every intermediate office through which the signals are to pass is instructed to have its wires connected in both directions exactly at the given hour, and to leave them so connected for ten minutes, without asking any further instructions. At the end of the line the instruments must be prepared at the appointed hour to receive the signals. All I have to do here is to place my clock in the circuit and send on the signals for ten minutes, commencing at eight o'clock. They are recorded at the other end of the line without further trouble."