The first formal meeting came on 3 August 1961, when Decker briefed Gilruth and his colleagues on "A Program Plan for a Titan Boosted Mercury Vehicle."3 The Martin plan was decidedly optimistic. For just under $48 million, NASA could buy nine boosters, developed, tested, and launched, the first launch to be within 18 months.4 What made this proposal so startling was that Titan II was still mostly promise. Martin's contract with the Air Force to develop the missile was scarcely a year old (June 1960), and Titan II's maiden flight was almost a year in the future. But the company had reason to believe that rapid progress was likely.
For one thing, much of the work and expense of Titan II development would be provided by the Air Force missile program. For another, some of the design and testing of changes needed to convert the missile to a booster for manned space flight had already been done, and more could be expected, as part of the Air Force Dyna-Soar program. The same simplicity and reliability that so appealed to Chamberlin in the Titan II, augmented by the redundant systems its greater power permitted it to carry, likewise promised a quick and successful development program.5
By the end of July 1961, when Silverstein approved the two-man Mark II, STG was all but ready to put that spacecraft on Titan II. Many of the rough spots had already been smoothed away; Martin had been talking not only to STG but to NASA Headquarters and the Air Force. The formal meeting of 3 August simply confirmed a nearly accomplished fact. At a senior staff meeting four days later, Gilruth commented on the vehicle's promise, particularly the greater power that made it "a desirable booster for a two-man spacecraft."6
The choice of a Titan to carry Mercury aloft may have done some violence to classical mythology. The giants of Greek myth were far removed in time and space from the Roman god. Those who first named Atlas and Titan in the mid-1950s were thinking of the symbolism of power, strength, and invincibility, qualities no less appropriate when their missiles were turned to more peaceful uses.7 Yet, in scouring classical mythology to name their missiles, and setting a precedent that NASA followed, they tapped a vein of symbolism far richer than they knew. Just as Atlas, though he bore heaven and Earth on his shoulders, was but a puny shadow of the Titans themselves, so was the Atlas booster far less powerful than the Titan II that succeeded it. Titan II could carry men to new heights, allowing them to say with Isaac Newton, "If I have seen farther, it is by standing on the shoulders of giants."8 Titan might also help to underscore the living relevance of Newtonian science in an age dominated by Einsteinian relativity and quantum mechanics. For if "the 'sputniks' constitute[d] the first  experimental proof of Newtonianism on a cosmic scale,"9 then the spacecraft carried aloft by Titan, shifting its orbital path in response to the commands of its pilots, offered an applied demonstration of Newtonian orbital mechanics. Eventually Titan II would carry the renamed Mercury on its shoulders in flights that soared far beyond the limits previously attained by mankind and would allow them to see farther than they had ever seen before.
The Agena B
Chamberlin's talks with Lockheed about Agena as a rendezvous target reflected the new orientation of Mark II work, toward a project rather than a spacecraft. Rendezvous was now a matter of intense concern within NASA. Despite its great promise, as stressed by the several committees that had discussed the subject during the spring and summer of 1961, it was still an unknown. Whether rendezvous would be as simple and useful in practice as it appeared to be in theory was a question that Mercury Mark II might well be able to answer.
Of other questions looking for answers, one of the most pressing involved the effects of extended stays in space on the human body. Mercury might lay some fears to rest, but its short missions could not allay doubts about long-term space dangers. Those doubts would become crucial in the Apollo program. A trip to the Moon and back demanded at least a week, compared to the four and a half hours of the longest Mercury mission then scheduled. Here was another area that Mark II might explore. The large increase in payload weight permitted by Titan II and the greater size of Mark II would allow the spacecraft to carry the extra supplies and batteries or fuel cells to provide electrical power for a mission of one or two weeks.
The end of the first phase of the paraglider development program in mid-August, which proved the feasibility of the concept for recovery of manned spacecraft,13 pointed to still another part Mark II might play. Mercury came back to Earth's surface via parachute.  Uncontrolled return made the ocean the best landing field. But this meant that each landing was a major undertaking in its own right, with fleets of ships and aircraft deployed to ensure the safe recovery of pilot and spacecraft. This clearly would not do if space flight were ever to become a routine enterprise. Fitted out with a paraglider system, Mercury Mark II might show the way to controlled recovery on land.
These were all, however, only ideas that needed to be hammered into specific proposals with goals, costs, and timetables. This was the purpose of the preliminary project development plan that Chamberlin and his co-workers began to prepare early in August 1961. The focus of their effort now shifted from the engineering design of an improved Mercury to framing the program such a capsule might serve. McDonnell reoriented work under its NASA study contract toward "basic and alternate missions for the MK-II Spacecraft" and increased the number of engineers assigned from 45 to 74.14 At the same time, three McDonnell engineers, led by Fred Sanders, journeyed to Langley, where Chamberlin, aided by James Rose and several contracting and scheduling specialists,* was getting started on the preliminary plan for a new project, using the Mercury Mark II two-man spacecraft.15 The first result was ready 14 August 1961.
* Sanders team stayed at Langley for two weeks; the other two members were Ervin S. Kisselburg and Gilbert G. Munroe. Munroe, who came to Virginia to work on spacecraft weight analyses, soon returned to an earlier assignment on the aircraft side of McDonnell. Frank G. Morgan, Jr., the company's marketing engineer for Mercury, was a frequent visitor to STG at this time, helping with cost estimates. Chamberlin's contract and scheduling help came from George F. MacDougall, Jr., Joseph V. Piland, Walter D. Wolhart, Lester Stewart, Nicholas Jevas, William C. Muhly, Richard F. Baillie, Donald L. Jacobs, Allen L. Grandfield, Paul M. Sturtevant, and Paul H. Kloetzer.
2 Paul E. Purser, notes on "Titan II Manned Booster," 29 June 1961; memos, Purser to Robert R. Gilruth, "Log for week of July 3, 1961," 10 July 1961, and "Log for week of July 17, 1961," 22 July 1961; Purser, interview, Houston, 14 March 1967; Walter C. Williams, interview, El Segundo, Calif., 16 May 1967.
3 James L. Decker, "A Program Plan for a Titan Boosted Mercury Vehicle," July 1961; Purser, notes on briefing, 3 Aug. 1961; memo, Purser to Gilruth, "Log for week of July 31, 1961," 10 Aug. 1961.
4 Decker, "A Program Plan"; Purser notes, 3 Aug. 1961. Attached to Pursers notes are "Mercury-Titan Program, Part II: Program Cost," 2 Aug. 1961, and a proposed program schedule, "Master Plan for Redundant System Booster," 1 Aug. 1961.
5 Decker, "A Program Plan"; Gemini-Titan II Air Force Launch Vehicle Press Handbook (Martin-Baltimore, ca. December 1964), p. II-1.
6 Jack C. Heberlig, "Notes on Senior Staff Meeting, Monday, August 7, 1961," 8 Aug. 1961, p. 3.
7 Lloyd Mallan, Peace Is a Three-Edged Sword (Englewood Cliffs, N.J., 1964), pp. 190-91; letter, R. L. Tonsing to Helen T. Wells, 28 Sept. 1965.
8 Letter, Isaac Newton to Robert Hooke, 5 Feb. 1675 6 in H. W. Turnbull and J. F. Scott, eds., The Correspondence of Isaac Newton 1 (Cambridge, Eng., 1959), p. 416, as cited in Alexandre Koyré, "An Unpublished Letter of Robert Hooke to Isaac Newton," Newtonian Studies (Cambridge, Mass., 1965), p. 227. As Koyré points out, and as many others have noted, the phrase did not originate with Newton and was, in fact, a commonplace; see Robert K. Merton, On the Shoulders of Giants: A Shandean Postscript (New York, 1965).
9 Alexandre Koyré, "Newton and Descartes," Newtonian Studies, p. 54.
10 letter, D. R. Church to James A. Chamberlin, 18 Aug. 1961.
11 R. Cargill Hall, "The Agena-Booster Satellite," presented at American Institute of Astronautics and Aeronautics, Boston, Mass., 2 Dec. 1966.
12 James T. Rose, interview, St. Louis, 13 April 1966.
13 Memo, Chamberlin to Dir., "Paraglider Landing System Design Studies; transmittal of final reports," 23 Aug. 1961; "Paraglider Development Program, Phase I: Final Report," North American SID 61-266, 15 Aug. 1961.
14 Letter, J. Y. Brown to Glenn F. Bailey, "Contract NAS 9-119, MK-11 Mercury Study Contract, Information Concerning," 832-16-12, 18 Aug. 1961, with enclosure, "NAS 9-119, MAC Job 832, Estimated Engineering Manhours Expenditures by Element," C-58496, ca. 6 Aug. 1961.
15 Purser memo, 10 Aug. 1961; memo, Purser to Gilruth, "Log for week of August 7, 1961," 15 Aug. 1961; Rose, Walter D. Wolhart, and William C. Muhly, telephone interviews, 13 Oct. 1972.