Robert P. Multhauf

F. W. Preston and William J. McGrath, Jr.

Although John Peate was born when Holcomb was only 33, and before that pioneer telescope-maker had produced his first instrument, he lived well into the time when American telescope-making had come of age. Before Peate’s death George Ellery Hale had begun his career as a promoter of large telescopes; indeed, the Yerkes 40-inch refractor was completed a year prior to Peate’s delivery of his own magnum opus, a 62-inch reflector, to The American University. For 34 years the University sought funds to finance the installation of this mirror, until it finally became obsolete as a result of advances in the technology of glass mirror making.

In 1934 it was sent by the American University to the Smithsonian Institution. About this time Dr. F. W. Preston undertook the difficult task of reconstructing Peate’s career and particularly the story of the great mirror. His results were published in the Bulletin of the American Ceramic Society in 1936.

With the gracious permission of Dr. Preston and the Bulletin, this article has been condensed, and augmented, for publication here by William J. McGrath, Jr., of the United States National Museum staff.

John Peate, bricklayer, Methodist minister, and amateur extraordinary in the art of telescope making, was the first born of Thomas and Mary Peate.[14] He was born on May 6, 1820, in the small northern Irish town of Drumskelt. When John was seven, his father, a mason, emigrated to Quebec, Canada, the first of several moves to cities in Canada and the United States, terminating in 1836 in Buffalo, New York, where the father was to spend the last seven years of his life.[15]

Nothing is known of the circumstances of John’s life during these early years, nor of his education. In 1836, at the age of 16, he entered his father’s trade as an apprentice bricklayer. He worked at this trade for about sixteen years, apparently intermittently, for he seems to have been a student at Oberlin College part of the time between 1842 and 1845.[16] In the latter year he married Mary Elizabeth Tilden of Buffalo.

Peate’s career as a bricklayer ended in 1851, when he became a full-time minister, having been converted to his mother’s religion. This came about in consequence of his attendance, when he was about 20 years old, at a Methodist revival. There he was “converted,” and, with characteristic energy and enthusiasm, plunged into his new religion. His attendance at Oberlin may have been connected with his preparation for the ministry. In any case, he started to preach in 1849, on trial with the Methodist Erie Conference, was ordained a deacon in 1851, and an elder two years later. From this time until he was made a supernumerary in 1894 he worked full-time as a minister.

The mobility which marked his early life was repeated in his ministerial career. Including his probationary term he held 19 different appointments in 14 cities and towns in northwestern Pennsylvania, northeastern Ohio, and southwestern New York. He was a successful and popular minister, and is said to have converted some 500 persons at one revival in Jamestown, New York. J. N. Fradenburgh, historian of the Erie Conference, begins his sketch of Peate’s life with the phrase, “Who has not heard of John Peate?”[17]

In 1859 Peate journeyed to Europe, visiting England and Ireland, and making a walking tour of western Europe and the Middle East. His biographer Fradenburgh hints that his interest in astronomy was aroused on this trip. In any event, upon his return home, he took up the study of the science. His fellow minister, R. N. Stubbs reported that “his library reveals that difficult and abstruse works became his delight.” At some point in the perusal of these “abstruse works,” Peate decided to concentrate on that basic tool, the telescope. It is possible that he first made a telescope, as many amateurs do, to advance himself in the study of astronomy, and only after completing it realized that his primary interest lay in the instruments rather than in the theoretical science. His natural aptitude for craftsmanship probably exerted a strong influence in this decision.

His first instrument was a 3-inch refractor which he made and mounted for his own use. This was about 1870. He next made either a 6-inch refractor or a 6-inch reflector, or perhaps both. One of these, if there were two, was mounted by Peate for use at Chautauqua and Jamestown, New York, and then used in his own observatory at Greenville. After his death it was taken to Salina, Kansas, by W. F. Hoyt, for a small observatory there.[18]

Thereafter Peate made reflectors exclusively. It is possible that he was influenced by the treatise on the making of silvered glass reflectors, by Dr. Henry Draper, published by the Smithsonian Institution in 1865, a work which led to a great improvement in the construction of reflectors in this country.[19]

Attempts to trace Peate’s mirrors have been singularly inconclusive. A 7-inch reflector sent to India was still in use in 1903.[20] A 12-inch reflector made for “Harriman University, Tennessee,” was evidently mounted, but no record even of the observatory has been found at the present time [1936].[21] A 15-inch mirror in a reflector located at Allegheny College in 1935 was probably made by Peate, although the College records do not show its origin, nor do they mention a 30.5-inch mirror which Peate was making for Allegheny College in 1891, according to an article in The Scientific American.[22] Definitely Peate’s was a 22-inch reflector found in about 1935, still in its packing case, at Thiel College, Greenville, Pennsylvania.[23]

Altogether, 10 lenses and mirrors (sometimes also described as “lenses”) have been traced. As many as 20 were ascribed to him by some sources at the time of his death. Of these only his magnum opus, the 62-inch mirror now in the Smithsonian Institution, can now be found. Most of them seem never to have been used, but this is not necessarily an indication of defects in the instruments. As our consideration of the 62-inch mirror will show, Peate was a competent maker. Nor is it a consequence of his being an amateur. Many of the large telescopes in the world in the mid-nineties had lenses and mirrors made by two other Americans, John Brashear and Alvin Clark, who, like Peate, entered telescope making as amateurs.[24] But they had the fortune to become associated with well known professional astronomers. Peate may have erred in presenting his reflectors to institutions unable to finance their installation. Perhaps his error was in presenting rather than selling them.

We come now to Dr. Peate’s greatest mirror, the 62-inch reflector. In September 1893 the annual meeting of the Erie Conference was held at Dubois, Pennsylvania. This was to be Dr. Peate’s last meeting as an active minister. In 1894 he would become a supernumerary, a position of semiretirement, after which he would retire. In order to honor the old minister and to mark the opening of a new Methodist university, American University, at Washington, D.C., it was decided to commission Peate to make a telescope mirror for the school. This was to be no ordinary reflector but the largest in the world.

While the facts surrounding this commission and its accomplishment are astounding in themselves it has inspired an even more remarkable legend, which, although rather unjust to the ability and good sense of Dr. Peate, indicates the impression his hobby had made on his contemporaries. According to this legend, John suddenly realized at the age of seventy-three that he must have something to occupy his time while retired.

Figure 11.—Standard Plate Glass Company, Butler, Pennsylvania, with x marking building where Peate’s 62-inch disc was cast. (From Preston, fig. 1.)

“What am I to do all the rest of my life?” he asked of the presiding officer of the meeting, Bishop Hurst, who was also chancellor of the newly founded University.

“Oh, study astronomy,” said the Bishop.

“Make a big telescope lens,” said Dr. Wythe.

Dr. Wythe, whose doctorate was in medicine, was a minister well known in the conference as an inventor and technologist. The legend continues that, urged on by Wythe, Peate announced to the conference, “I will make for the new University the largest telescope lens in the world, if you will defray the out of pocket expenses.”

“Well, how big a lens can you make?” asked the Bishop.

“Oh, as big as that chart on the wall,” said Peate.

“Get a rule and measure the chart.”

The chart was 62 inches across.

“Offer accepted. One 62-inch reflecting telescope from Dr. Peate,” ordered the Bishop.[25]

The minutes of the conference state:[26]

Although he was 73 years old Peate was in good health and had tremendous vitality for one his age. He had already made a number of large mirrors, so that he could estimate the amount of time and energy he would expend in this work. He knew that if he retained his health for the next few years he could complete it.

With his typical planned enthusiasm he started his preparations. He wrote to his usual supplier St. Gobain of France asking the price of a glass blank large enough for a mirror of this size.[27] They quoted a price of $18,000—more, obviously, than he could afford. He then canvassed the glassmakers of Pittsburgh, the center of American glassmaking. However, the Pittsburgh firms had little experience in optical glass, especially of this size, and none would consider making the blank.

Having been rebuffed in Pittsburgh, he approached the Standard Plate Glass Company of Butler, Pennsylvania. Plate glass making, at least profitable plate glass making, was new in America and the Standard was one of the newer companies. Moreover, it was reputed one of the best plate glass makers in the country. Peate wrote to H. C. Tilton, general manager of the plant, asking him for a disc of glass without bubble or flaw 62 inches in diameter and 7 inches thick. He further advised him that he would see him in a few days. Tilton’s experience and that of his top supervisors was limited to the business of making ordinary plate glass. Therefore, he sought advice as to the feasibility of this fantastic project. He consulted George Howard, maintenance engineer of the plant, who had graduated from Cornell only a year before. George Howard, later to become noted as an inventor of glassmaking machinery, was at this time simply an optimistic young engineer.

“Howard, here’s a man at Greenville who wants us to cast him a disc 62 inches in diameter and 7 inches thick. Is that possible?”

Howard calculated the cubical contents of the proposed disc and replied that it was just barely possible. He didn’t see any particular difficulty in it. He thought the first few attempts might fail but felt that they could cast it successfully. Howard was later to ascribe his success more to his optimism and ignorance, rather than to any particular innovation he made. After being reassured by Howard, Tilton continued “Well, this Dr. Peate is coming down here tomorrow and he wants a quotation. How much do you think we ought to ask?”

“We’ll have some special apparatus to make and some experimenting to do. Then we’ll probably lose two or three pots of glass. I think you’d better ask him $800.” Howard thought that this was plenty. Tilton, however, was more cautious and doubled the price. Peate arrived in Butler on schedule. When Tilton named his price, Peate, of course, agreed instantly. Tilton was somewhat shocked and probably would have been more so had he known what St. Goubain had asked. At any rate the contract was placed with Standard, apparently in October 1894.

Having obtained a maker for his disc Peate immediately began making arrangements to prepare the disc. He contracted with the machine shop of a John Hodge for the tools with which the mirror would be worked. This small firm, The Hodge Manufacturing Co., employed only four men besides the owner. Among these was Frank A’Hearn, then just a boy, who became the prime source for details of the tools used by Peate in this work. Starting in November 1894 notes such as, “worked for Dr. Peate 3½ hours” begin to appear in his workbook.[28]

The Hodge company made several (probably three) grinding tools for Peate. One was about 12 inches in diameter, and was to be used by hand. Two of the larger tools were provided with the male member of a ball and socket joint and were to be power driven. They were 30 and 48 inches in diameter, respectively. The largest was grooved to a waffle-like surface on its convex face. These grooves were about ½ inch wide and 3/16 inch deep. This pattern was ground by placing the tool face up on a wheeled buggy, which rode on cambered oak rails. As it was pushed along the length of the rail the grinding wheel on the radius arm cut one groove. When the groove had been cut, the radius arm was moved 2 inches along a line shaft and another groove cut. When all the grooves had been cut in one direction the tool was turned 90 degrees on the buggy and the other set of grooves was ground. The grinding of this tool took many weeks, and making the tools and apparatus for Peate may have kept Hodge busy for nearly six months.[29]

The history of Peate’s 62-inch mirror probably would have remained as obscure as that of his others except for the furor which arose over casting the disc. The Erie Conference made no attempt to publicize this project, and both Hodge Manufacturing and Standard Plate Glass accepted Dr. Peate’s contracts as somewhat unusual but hardly newsworthy jobs. But when the glass trade became aware of Standard’s intention to cast this disc, a mighty outcry arose. Instead of encouraging Standard to complete this novel task the National Glass Budget, one of the leading trade journals, reviled them as “bumpkins” for attempting something that even the great glassmakers of Europe would not do.

It is hard to imagine why the trade journal so strenuously objected to Standard’s attempt. It has been suggested that it derived from the fact that Standard Plate Glass just previous to that time had refused to join in a combination of Pittsburgh companies which had set up a glass trust.[30] Or it is possible that the young industry was afraid that an overly ambitious project doomed to failure might open American glassmaking to European ridicule and so harm the entire American industry. Whatever the reason, the Budget ridiculed Standard Plate Glass, and later Dr. Peate, for the attempt. They argued that it could not be done, but that if it were possible Pittsburgh would be the logical place to try it. Criticism and unfavorable comment came from other sources also, including “university professors from Meadville” (evidently Allegheny College).[31] Nonetheless, Standard Plate Glass started the project.

George Howard was in charge of the casting operation. He planned to use the glass from a pot regularly used in the routine manufacture of plate glass. However, certain modifications were introduced in the procedure. The glass was to be poured on the traveling casting table, upon which was placed a circular mold made up of two semicircles of a special charcoal iron obtained from Philadelphia. This iron was not apt to generate bubbles of gas when in contact with the molten glass.

The iron mold was hinged at one joint of the semicircles, and the other joint was bolted. After the cast was poured it would be allowed to cool somewhat. When it was judged cool enough, it would be pushed into a kiln to be annealed. After it had remained in the kiln a certain length of time—again based simply on judgement—a quantity of pre-heated sand was to be poured over the mold as insulation. A further innovation was the use of a zinc sheet placed on the underside of the mold to avoid the possibility of trouble from grease on the casting table. This was the initial plan of operation.

Sometime early in 1895 the first attempt was made. It was an immediate failure. The zinc sheet, intended to protect the cast from grease, volatilized when the molten glass was poured on it, bubbled up through the glass, and, of course, ruined the cast.

The second attempt was evidently made sometime in March. The casting itself was successful. Sand had been substituted for the zinc sheet. The cast was placed in the kiln, and when it was thought to be set the insulating sand was poured over it. After a time variously estimated at from 4 to 11 days, the cast was considered sufficiently annealed, and was examined.

When the sand was removed, the disc was found in fragments. There was also a large concavity in what would have been the face of the disc. The sand had been poured over it before the glass was sufficiently set. However, the disc had been destroyed by its iron mold. The mold had contracted against the disc, bending the bolt and deforming the hinges, and this tremendous pressure had shattered the glass. The next issue of the trade paper jubilantly noted the failures. They also included Dr. Peate in their derision. They said in effect that at least this experience would save the old preacher the waste of many years of time and effort.[32]

This slur on their most esteemed citizen brought the Greenville papers into the battle. The Budget had also made the mistake of implying that any number of Pittsburgh manufacturers were willing and able to make the disc. John Morrison, at that time editor of the Greenville Advance Argus, and source of much of our information regarding this controversy, immediately called the bluff of the trade paper, which was able to supply but one name, that of a George A. McBeth Company. This firm promptly declined without qualification. Later the name of the Phillips Semner Co. was given, and this firm guaranteed a perfect disc within 60 days for a “remunerative price,” but would not state what this price was.[33] Therefore Dr. Peate could not deal with the firm.

Although the hue and cry continued for a few more weeks, the battle was really over, for Howard was soon to cast his disc. He had replaced the iron bolts in his mold with bolts of red oak dipped in nitric acid and then charred. The purpose of this was to relieve the strain on the glass by having the wooden pegs break as the mold contracted.

The third cast was in the kiln and in process of being annealed when Howard read in the Budget an article that set forth the difficulties of successfully casting optical glass. This article was anonymous and was obviously the work of an expert; it is thought to have been written by John Brashear.[34] Although Howard was thoroughly discouraged by this article, the cast had already been made and no harm could be done now by allowing it to cool and be examined.

In May 1895 Howard, with the workmen, opened the kiln. The mold was loose, so the pegs had sheared as expected. When the sand was removed the disc was found to be whole. A close inspection revealed no obvious faults. The disc was gently carried to an inspection room and Dr. Peate was immediately sent for. He arrived, examined the disc for a moment, then said, “Give me a hammer.” Before anyone could move he seized a nearby hatchet and knocked off the sprue, or tail left as the pot was removed from the mold. The onlookers feared the lens would “explode,” as predicted by its detractors, but the only result was the removal of the tail, as Dr. Peate expected.[35]

The Budget was still saying it couldn’t be done. Commenting on a May 1, 1895, announcement of the removal of the disc from the kiln, the paper seized on the fact that the disc was still warm to predict that it would be shattered before Peate could examine it, and reiterated its low opinion of Standard Plate. By the time this issue was in the hands of its readers however, the disc had been inspected and approved by Peate.

Newspapers in Pittsburgh and elsewhere carried the news of the great American disc. The embarrassed Budget replied that it was not talking about the mere casting of the disc but the completion of the mirror. It feigned surprise that this was all that was to be done in Butler. Even as late as May 24, 1895, the Butler Democratic Herald was still defending its town. It concluded an editorial on the issue thus:

A week before this, however, the success of this casting had been made more or less official by an announcement to that effect in the May 17, 1895, issue of Science, a publication of the American Association for the Advancement of Science and probably the most highly regarded scientific paper of the time.

On June 1, 1895, Standard Plate rendered Peate an invoice, not for $1600, but for $450. Evidently their work was done at cost. The disc was now removed to Greenville where Dr. Peate had erected a shop to grind, polish, and figure it. As the disc was slightly out of round the first operation was to make it perfectly circular. Peate did this roughly by spalling off pieces of the edge with his bricklayer’s hammer. The final rounding was done with the aid of the iron hoops that had made the mold. Dr. Peate fed steel shot between the edge of the disc and the iron semicircles. He rotated the disc on the turntable and thus rounded it off.

After this had been done he commenced the rough grinding. Using the large checkerboard tool, steel shot, and levigated emery Dr. Peate ground out a rough hollow. This took only a few days. George Howard stated that the depth of the concavity was about ? inch and the shape correct to within about 1/10,000 inch. The calculated concavity of the mirror would be 6/10 inch. Peate evidently used the usual method in polishing the large mirror, that is, he covered the tool face with pitch and used rouge (iron oxide) as the abrasive. This method had been used for many years before this time and is still in use today.

The figuring, which consists of removing high spots to achieve a truly parabolic contour, probably took the longest time to complete. A mirror must be continually tested as this polishing is being done, and since the polishing warms the glass and distorts its shape, it is necessary to allow a long time for the glass to cool before it can be tested. Peate estimated that polishing and figuring the mirror took 750 hours.[36]

We do not have a really accurate account of how he tested the mirror. Unfortunately none of the eyewitnesses to these tests had any knowledge of optics or of standard testing procedure. The information of those who had such knowledge is all at least secondhand and sometimes even more remote. J. W. Fecker, successor to Brashear,[37] who was one of a group that examined the mirror in 1923, states that Peate did not use the knife edge test but that he did use a pin with a hole in its head in one of the tests used at that time.

A variety of different tests and diversions with the mirror have been reported. Dr. Peate would entertain visitors in various ways. One of these was to train the mirror on an apple orchard in a valley a few miles away. In another Peate would pull out one of his whiskers and hang it on a fence nearly a quarter of a mile away. Peate himself tells of the time spent in testing the mirror, but does not go into detail about the procedure. He does mention a testing table that stood about 75 feet away from the revolving table on which the mirror rested. He says further that the mirror was tested “in all ways known, in the shop and on a pin and a watch dial a thousand feet distant.” Of these only the pin test seems to have been a conventional one.[38]

After the polishing, the mirror was silvered. Said Peate: “It was silvered and tried on the heavens in the starless region under Corvus, and under the very imperfect management of the mirror on telescopic stars, the report was as good as could be expected.”[39] Dr. Peate must have spent some time testing it on the stars. The mirror was evidently completed sometime late in summer of 1897, and when Peate was satisfied that it was as perfect as possible, he made arrangements to send it to American University. He also designed the shipping case to protect it on the trip to Washington. It is described in the University paper as follows:[40]

After waiting for the case, he encountered a further delay by reason of the fact that the express company had no office at Greenville. However the great glass finally was loaded on the train, and on August 24, 1898, it arrived safely at American University.

Although all parties concerned in this project seemed optimistic, no provision for mounting the mirror had yet been made. The University paper which announced the safe arrival of the glass hoped, at a later date, that—

This donor was never to appear. Five years later, in announcing the death of Peate, the Courier was still appealing for funds to mount the mirror. Late in 1903 it announced that a gentleman in Pennsylvania would contribute $100,000 to defray the cost of an observatory to house the mirror, but nothing further was ever heard of this gentleman. Earlier, before the mirror had been made, the Reverend H. G. Sedgwick of Nashville, Tennessee, had offered to mount and equip the mirror on the same terms under which Peate had made it. That is, he would do the work if someone would donate the cost and the material. But of this offer, too, nothing further was heard. Possibly he died before the mirror was completed.

The mirror was to remain untouched for some 24 years. In 1922 the “Greenville Roundtable,” a group reportedly founded by Dr. Peate, allocated $90 to the Reverend H. G. Dodds to investigate the disposition of the mirror. In that same year the Erie Conference appointed Dodds a committee of one to report on the same matter. Dodds visited American University and conferred with the chancellors. They checked the mirror and it seemed to be in good shape. Dodds then went to Warner and Swasey, in Cleveland, Ohio, where he attempted to discover what it would cost to mount the mirror and provide an observatory. But he learned nothing there. Dodds knew nothing either of astronomy or of glass and his lack of knowledge did not inspire confidence in his mission. He did note a peculiar phenomenon, that people seemed suspicious of the mirror in itself without knowing anything about its actual condition.[41]

Shortly after Dodds’ failure to secure a user for the mirror the Perkins Observatory at Ohio Wesleyan University, which planned to add a large reflecting telescope, became interested in it. Dr. Clifford C. Crump, director of the Perkins Observatory, J. W. Fecker, then president of the J. W. Fecker Company, and A. N. Finn and A. Q. Tool, of the National Bureau of Standards, inspected the glass at American University. They found it remarkably free of bubbles and similar defects. Due to a lack of facilities they were unable to test the mirror optically, so that no comment was made on either the polishing or the correctness of the figure. It was, however, found badly strained due to poor annealing, and Fecker advised against using it, as it would have to be re-annealed. If this were done, some refiguring would also be necessary. After this rather expensive renovation it would remain a rather thin, flexible glass and not equal to modern standards. The Perkins Observatory consequently decided rather to use a mirror cast and finished under the supervision of the Bureau of Standards.[42]

This was the last attempt to use the mirror. It remained at American University until the mid 30’s, when it was placed in the Smithsonian Institution. It was still, in February 1935, the largest mirror ever cast and polished in the United States.

Let us return now to Dr. Peate. After seeing the mirror safely stored at American University he returned to Greenville, Pennsylvania. Then 78 years old, still in good health and very active, he was to live for 5 more years.

To the end of his life he maintained his interest in astronomy, and was optimistic about the possibility of his great mirror eventually being mounted and used. In 1900 at the age of 80 he decided to see Europe once again. His prime objective on this trip was undoubtedly the Paris Exposition of 1900, where one of the main attractions was a huge telescope made by Gautier. It had a refracting objective of 49.2 inches, mounted horizontally, the largest refractor yet made. Strangely enough this much publicized telescope was never used either. After the exposition was over the backers became bankrupt and the instrument was dismantled and sold for scrap.

Dr. Peate with his wide range of knowledge and his conversational ability delighted and puzzled his fellow passengers on the boat to and from Europe. They guessed that he was an educator, a scientist, or statesman but he denied all this saying, “no, I’m only a bricklayer.”

Dr. Peate lived three years after this trip, dying on March 24, 1903. His good health and physical vigor never left him till almost the moment of his death; as shortly as a week before, he had conducted a funeral service.

It would be rather easy to dismiss him as a harmless fanatic except that everything known of him indicates that he was not. It is reasonable to believe that his mirrors were made more in the hope than in the certain expectation that they would stimulate the study of astronomy in the institutions receiving them. He was probably well aware of the difficulties of establishing so large a telescope at a newly founded institution such as American University, and, content in the knowledge that he had done his part, could only hope that others might be inspired to do likewise.

Dr. Peate’s great mirror will shortly be put to use in a manner that could hardly have been predicted by its maker. It has been in the Smithsonian Institution for over 20 years. The huge glass will form a part of the exhibition of optics and astronomy in the new Museum of History and Technology that the Smithsonian Institution will open to the public about 1962. There it will be seen by some millions of persons each year. Because of its spectacular size it should catch the attention of most museum visitors. Surely it will awaken in more than one potentially able worker an interest in astronomy. If so, it will have accomplished Dr. Peate’s purpose.