including the special expeditions of the Coast Survey to Liverpool, Professor Walker remarks: "I am convinced that there is no possible interpretation of them which will place the results below his reported value, 4h. 44m. 30.15., for the longitude of Harvard observatory from Greenwich observatory. "The longitude of Harvard observatory, by moon culminations at Harvard observatory, Dorchester, Hudson, Wilkes' observatory, and the Washington observatory, comes out very uniformly about 4h. 44m. 28.4s., leaving a discrepancy below the results by chronometers of 2.78. This discrepancy will, I hope, be explained in time by persevering efforts.” Mr. Walker gives an abstract of his report on longitude, which will be found in Appendix No. 26. A meteorological register was kept at Causten's station, by Mr. B. F. West, recording, for thirty-two days, observations for temperature of the air, moisture, atmospheric pressure, and the force, amount, and direction of winds and clouds. Reconnaissance, primary triangulation, &c.-Major Henry Prince, United States army, assistant in the coast survey, made, during the earlier part of the season embraced in this report, an extended reconnaissance of the eastern shore of Maryland and Virginia-the purpose of which was to arrive at a mode of connecting the secondary triangulation of the Atlantic shore with that of the Chesapeake. The results of his examination show great difficulties in making the connexion high up the peninsula, for want of suitable natural elevations for signals, and on account of the heavy cutting involved in the use of any station on the main land. It therefore appears advisable, as it is reported practicable, to make the connexion by observing from island stations on either side-upon Drummondtown or some point where the peninsula is narrow-or to postpone the connexion until Cape Charles is reached by the Chesapeake and by the outside triangulations. From this reconnaissance, Major Prince passed to that of Pamplico sound and others of importance. Assistant Edmund Blunt, with a party for primary triangulation, was engaged in the lower part of Chesapeake bay for the greater part of three months, June to August; afterwards proceeding north for the triangulation of the Hudson river, and returning to this section in No⚫vember. Mr. Blunt's operations in this section were the observations for triangulation and the reconnaissances appropriate to form a judicious scheme, and to establish points for hydrographical and topographical purposes. The triangulation of the season extends from Wolf Trap station (intermediate between York and Rappahannock rivers) south towards the entrance of Chesapeake bay, at which some preliminary determinations were made. A reference to the general sketch C, will show that it has adopted as primary points the principal capes and light-houses. Care was taken in all cases to mark the points used in a permanent manner for future reference. The statistics of Mr. Blunt show 18 primary angles measured, and 67 others—in all, 136 series of angles were measured by 1,478 observations. The season's work covered an area of 400 square miles. Secondary triangulation.-Assistant John Farley has continued this portion of the work along the outer coast of Virginia. His party, en gaged during October and November, 1850, and June, July, and August, 1851, suspended operations at the end of August on account of health, but returned to the field in October. In the intervals of withdrawal they have been occupied in the computation of previous work. The triangulation has been continued (see sketch C) from Joynes' station, near Drummondtown, Accomac county, to Sand shoals, opposite Eastville, in Northampton county, Virginia, and within about 18 miles of Cape Charles. It covers an area of 150 square miles, “by the occupation of 10 stations, with 42 angles, and 1,100 intersections, on 51 lines of sight." Mr. Farley adds that, at the request of the Fifth Auditor, Mr. Pleasanton, "a point has been incidentally established upon the public reservation for a light on Hog island, in Northampton county-subject to be received as the centre of the proposed light-house; which point, if accepted, will have determined the latitude and longitude of the same." Assistant Farley was aided by Mr. George H. Bagwell. Topography, (sketch C.)-Four plane-table parties (one of which was double) have been in the field during the available portions of the year. Their operations have been as follows: 1. After the date of my report of last year, and in April, May, and June of the present year, assistant J. B. Glück continued the revision of the topography of the shores of the Patapsco. His sheets comprise an area of 26 square miles, and an extent of shore-line of 98 miles. The Coast Survey schooner Nautilus was assigned as a means of transportation for his party. Mr. Glück is now (October 15) under instructions to return to this section for the completion of this work, which is essential to the publication of the chart of Baltimore harbor and the Patapsco river, already delayed by circumstances which could neither be foreseen nor controlled. 2. A double topographical party was in the field under sub-assistant John Seib until the latter part of December, 1850; was then occupied in office work, and resumed its field duties in May, 1851. Sub-assistant S. A. Wainwright returned to this party in August, having been meantime in section V. Mr. G. W. Parrish and Mr. John H. Wise have been aiding Mr. Seib. The party have had in use the Coast Survey schooner Wave. The topography executed this season in the Chesapeake bay, including the interior of the coast between the Potomac and Rappahannock rivers, extends over the latter, and along the shore to within a few miles of York river, and on the opposite coast covers the shore and islands from the immediate vicinity of the Maryland line southward to a point about 15 miles from Cape Charles. Mr. Seib's account of the progress and general character of the work is given more in detail, by reference to the numbers of the plane-table sheets, as follows, (see general sketch C): Sheets Nos. 40 and 41, (western shore between the Potomac and Rappahannock rivers,) and Nos. 42 and 43, (eastern shore and islands of Pocomoke sound, and the neighboring portion of the Chesapeake,) were completed during the fall and winter of 1850. Sheets Nos. 46 and 47 embrace the survey of the main shore of Chesapeake bay, from Windmill Point to Wolf Trap, the shore of the mouth of the Rappahannock, on the north for three miles, and or the south for two miles, with the topography of Hill's bay, Milford Haven, Gwinn's island, and Stingray Point. The country is slightly elevated, intersected by creeks, coves, and ponds, and thickly settled. No. 48, embracing the main eastern shore of the Chesapeake bay, from Sandy Point to Rose Mary, furnishes its topography, and that of the creeks included. The country is in part even and swampy-in part sandy and slightly uneven. The banks along the main shore vary from five to twenty feet in height. No. 45. This sheet is completed, comprising the shores and topography from Sykes' island to Deep creek. A portion of this work was executed by Mr. Wainwright. Mr. Seib furnishes the following statistics for the year: Shore-line of bay, sound, creeks, and coves.. Area of country.. .433 miles. 91 square miles. The office-work of the party (in which Mr. Seib and Mr. Wainwright were occupied during the winter and spring of 1851) consisted in inking and lettering the plane-table sheets of the previous season. 3. The statistics above given do not include the separate operations of sub-assistant S. A. Wainwright, who entered in August upon the topography of the eastern (Chesapeake) shore of Virginia, having been previously engaged in another section. His work for the season, up to October, is embraced in the plane-table sheet No. 45. It extends from Sykes' island to Guilford signal, along 44 miles of shore-line. Mr. Wainwright is going on with Pocomoke sound, and will pass, if practicable, to the western shore of Virginia, before the close of the season. 4. Assistant G. D. Wise, after closing his work on the coast of South Carolina, passed, May 8, to the survey of the Atlantic coast of Maryland and Virginia. The party was broken up about the first of July, by the sickness of Mr. Wise and some of his men. The season's work is included between Lonesome Hill station, on the coast of Maryland, near the Virginia line, and Chincoteague inlet, Virginia, extending over fourteen miles of coast, along fifty miles of shore-line. The area embraced is twenty-five square miles. Assistant Wise returned to the field, and took charge, October 15, of the party on the Atlantic coast of Virginia, whose operations I am next about to notice. 5. Mr. W. M. Johnson having been engaged from December, 1850, to June, 1851, in Section VIII, as aid to assistant Greenwell, and subsequently in office-work pertaining to that section, was transferred, August 12, to a party in Section III, (then under sub-assistant J. M. Wampler,) of which, in a few days after, he succeeded to the charge. His work, up to October, embraces Wallop's and Assawaman islands, and a portion of Matomkin, extending south to the point marked South Gargathy, on the seacoast of Virginia, running inland a mile and a half, or two miles, (far enough to give an accurate idea of the topography of the entire back country) and being the continuation southward of the work just reported as executed by assistant Wise. It embraces an area of 21 square miles, and extends along 65 miles of shore-line, and 6 of roads. On the general character of this portion of the coast, Mr. Johnson remarks: "The main land is about twenty feet above the level of the ocean, sloping gradually from the water's edge. Between the islands. and the main land lies a body of marsh, intersected by numerous creeks, bays, &c., and which is overflowed at every high water." Hydrography.-Lieutenant Commanding John J. Almy, United States navy, assistant in the coast survey, has prosecuted, during the greater part of the season, the outside hydrography of the seacoast of Virginia. The steamer Legaré and the schooner Graham, belonging to the coast survey, have been placed under his command for this service. The state of the season rendering it dangerous to continue outside work with the steamer, the vessel and party were transferred early in September to the hydrography of Chesapeake bay. The Graham being of such light draught as easily to secure shelter in the inlets, was left outside to do some filling up and finishing off with her boats-thence to pass to the bay, and carry on the inside soundings there. The character and progress of the work may be gathered from the sketch C, No. 3, (on which it embraces the coast between the points marked Lonesome Hill and South Gargathy,) and from the following description by Lieutenant Commanding Almy: "I have completed the outside work down to South Gargathy, and in a direction southeast by east from this point, a distance of eleven miles seaward, where the tops of the trees in a clear day can just be seen from the deck of the steamer-the land being very low about here. This makes for my outside work this season eighteen nautical miles of in-shore soundings by the coast to the southward; and twenty miles from the southeast point of outside soundings last year to their termination point of this year. "The season's work has covered Chincoteague shoals, and been brought into smooth, regular sourdings, which continue down to the Chesapeake bay. These Chincoteague shoals appear to be the terror of all navigators who have to pess anywhere near them; and frequent inquiries have been made of us respecting their survey. The soundings which embrace all of these shoals are now completed." The hydrographic work in Cheasapeake bay, resumed by Lieutenant Commanding Almy, September 20, was continued until late in November. lis progress is thus described, (see also sketch C): "The soundings in Chesapeake bay have been entirely completed as far down as a s.raight line drawn-which is very nearly due east and west-from Windmill point, (point of triangulation,) on the west side of the bay. Then south of the east and west line, on the west side of the bay. The soundings have been completed as far down as Wolf Trap, (point of triangulation,) and on a line due east from this, as far as the meridian of 76° 04', which is about two-thirds of the way across the bay from the west side." The following statistics of the work are reported by Lieutenant Commanding Almy: Area sounded, out, square miles 286 Seacoast work. Bay work. 247 28,610 849 ..31,052 Number of soundings made by steamer and boats In the outside soundings, 27 different specimens, and in the inside 13, have been obtained and placed in bottles, in duplicate, provided at the Coast Survey office. A sketch of the outside hydrography, executed by Lieutenant Commanding Almy, will be published immediately. From the indications afforded by the track of three bottles, which were thrown overboard by Lieutenant Commanding Almy at different times, with dates marked, and which have since been picked up, it would appear that there is a general southwesterly current setting along the eastern (Atlantic) coast of Virginia, but quite moderate in strength. On his return from Section VIII, Lieutenant Commanding B. F. Sands, United States navy, assistant in the coast survey, was directed to commence the survey of the approaches to the Chesapeake; and the steamer Walker, which he had used in Louisiana, requiring repairs, the Coast Survey schooners Nautilus and Meredith were assigned for his work. The arrangements for the transfer of the crews of the vessels were made by the 13th of August, and the work continued until the close of September. The following extract from the report of Lieutenant Commanding Sands will show what has been accomplished: "As the season was so far advanced that it was not probable we would have much good weather to complete any particular part of the section, I determined to run as many lines of soundings as possible over the 'Middle Ground' between the capes, confining myself to the shoal water, as that part was least known, even to the pilots. "The weather was not favorable to very extensive work-the easterly winds, prevailing, made it frequently too rough for sounding; but we succeeded in running two hundred and sixty-eight miles of soundings, and in making ten thousand two hundred and thirty-eight casts of the lead in an area of sixty-five square miles, which will show the general configuration of a part of that great thoroughfare hitherto so little known. The tides were observed at two stations, and two positions occupied for preliminary current stations; the weather preventing further observations upon the currents, as was intended. "A short season of smooth weather would enable us to finish this interesting portion of the approaches to this extensive bay, a knowledge of which would be of the greatest importance to the commerce of the Chesapeake and James river. The unfavorable weather would not admit of so extended a survey as to enable me to make reliable sailing directions; but the publication of a preliminary sketch of the work done would prove interesting to the commercial community." The recommendation with which the extract closes has been adopted, and the sketch will be reduced and engraved to accompany this report, (sketch C, No. 2.) It is due to Lieutenant Commanding Sands and his |