1 68 REPORTS OP INVEISTIGATIONS AND PROJECTS. 



The vessel will have full sail-power, being rigged as a brigantine, carrying 

 just under 12,900 square feet of plain sail. In addition to this there will be 

 an auxiliary power plant, constructed of non-magnetic materials as far as 

 possible and consisting of a 6-cylinder internal-combustion engine capable of 

 developing 125 indicated horsepower at 350 revolutions per minute, which, 

 driving a feathering propeller of special design, will give the vessel a speed of 

 6 knots in calm weather. The engine will be operated by gas generated in a 

 producer gas-plant. The vessel will carry 25 tons of coal in her bunkers, 

 which will give her a cruising radius of 2,000 nautical miles at a speed of 6 

 knots. 



All living quarters will be below, the ventilation and lighting to be obtained 

 by means of a cabin trunk on deck about 42 feet 8 inches in length, 16 feet 6 

 inches in width and 3 feet in height, and safety will be secured by means of 6 

 transverse watertight bulkheads dividing the vessel into 7 compartments. 

 The sailing officers' and crew's quarters will be forward, 42 feet in length and 

 occupying the full width of the vessel ; next will be the quarters for the scien- 

 tific staff, 38 feet in length and extending the full width of the vessel ; and 

 abaft of this will be the machinery space 2^ feet in length. The living quar- 

 ters have been planned to give good accommodations for all, and will be 

 fitted with all necessary conveniences for long cruises. 



The observation room and magnetic observatories are located on main deck 

 amidships, and consist of a central observation room with circular observa- 

 tories forward and aft of it. The observation room will be 14 feet 6 inches 

 long and 16 feet wide, and the observatories will be circular, 7 feet 6 inches 

 in diameter, each fitted with a revolving dome, constructed of bronze frame- 

 work and plate-glass and arranged so as to permit, whenever possible, sight- 

 ing on celestial or terrestrial objects in magnetic declination work. The 

 joiner-work will be in white pine painted, with hardwood trimmings finished 

 bright. 



The general principle followed in the arrangement of the magnetic instru- 

 ments is to locate them where the effect of the magnetic material necessarily 

 remaining in the machinery, etc., will be of the order of the error of observa- 

 tion, and to secure independent, duplicate determinations of each magnetic 

 element, as far as possible. 



The plans and specifications have been prepared, in consultation with the 

 Department, by Mr. Henry Gielow, naval architect and engineer, of New 

 York City. The construction is to be begun in December, 1908, and the date 

 set for completion is July i, 1909. 



Plate 10, showing the Carnegie as she will appear under sail, was pre- 

 pared from a wash drawing made to scale from the working plans by the New 

 York artist, Mr. C. McKnight Smith, under the direction of the naval archi- 

 tect, Mr. Gielow. 



