Washington, May 2—P. M.  
The police resources of the country have been fairly tested during the past two weeks. Under the circumstances, the shrewdness and energy of both municipal and national detectives have been proven good. The latter body has had a too partial share of the applause thus far, while the great efforts of our New-York and other officers have been overlooked. In the crowning success of Doherty, Conger, and Baker on the Virginia side of the water we have forgotten the as vigorous and better sustained pursuit on the Maryland side.
 
Yet the Secretary of War has thanked all concerned, especially referring to many excellent leaders in the long hunt through Charles and St. Mary's counties. Here the military and civil forces together amounted to quite a small army, and constituted by far the largest police organization ever known on this side of the Atlantic.
 
I think the adventures and expedients of these public servants worthy of a column. It would be out of all proportion to pass them by when we devote a dozen lines to every petty larceny and shoplifting.
 
On the Friday night of the murder the departments were absolutely paralyzed. The murderers had three good hours for escape; they had evaded the pursuit of lightning by snapping the telegraph wires, and rumor filled the town with so many reports that the first valuable hours, which should have been used to follow hard after them, were consumed in feverish efforts to know the real extent of the assassination.
 
Immediately afterwards, however, or on Saturday morning early, the provost and special police force got on the scent, and military in squads were dispatched close upon their heels.
 
Three grand pursuits wore organized: one reaching up the north bank of the Potomac toward Chain bridge, to prevent escape by that direction into Virginia, where Mosby, it was suspected, waited to hail the murderers;
 
A second starting from Richmond, Va., northward, forming a broad advancing picket or skirmish line between the Blue Ridge and the broad sea-running streams;
 
A third to scour the peninsula towards Point Lookout.
 
The latter region became the only one well examined; the northern expedition failed until advised from below to capture Atzerott, and failed, to capture Payne. Yet there were cogent probabilities that the assassin had taken this route; far Mosby would have given them the right hand of fellowship.
 
When that guerrilla heard of Booth's feat, said Captain Jett, he exclaimed:
 
"Now, by——! I could take that man in my arms."
 
Washington, as a precautionary measure, was doubly picketed at once; the authorities in all northern towns advised of the personnel of the murderer, and requests made of the detective chiefs in Baltimore, Philadelphia, and New-York, to forward to Washington without delay their best decoys.
 
A court of inquiry was organized on the moment, and early in the week succeeding rewards were offered. An individual, and not the government, offered the first rewards.
 
There were two men without whom the hunt would have gone astray many times.
 
John S. Young, chief of the New-York detective force, a powerful and resolute man, whose great weight and strength are matched by boundless energy, and both subordinate to a head as clear as the keen and searching warrant of his eye. This man has been in familiar converse with every rebel agent in the Canadas, and is feared by them as they fear the fates of Beall and Kennedy. Without being a sensationist, he has probably rendered the cleverest services of the war to the general government. They sent for him immediately after the tragedy, and he stopped on the way for his old police companion, Marshal Murray. The latter's face and figure are familiar to all who know New-York; he resembles an admiral on his quarter-deck; he is a detective of fair and excellent repute, and has a somewhat novel pride in what he calls "the most beautiful gallows in the United States."
 
These officials were ordered to visit Colonel Ingraham's office and examine the little evidence on hand. They and their tried officers formed a junction on Sunday afternoon with the large detective force of Provost-Marshal Major O'Bierne. The latter commands the District of Columbia civil and military police. He is a New-Yorker and has been shot through the body in the field.
 
The detective force of Young and Murray consisted of Officers Radford,
Kelso, Elder, and Hoey, of New-York; Deputy-Marshal Newcome, formerly of
THE WORLD'S city staff; Officers Joseph Pierson and West, of Baltimore.
 
Major O'Bierne's immediate aids were Detectives John Lee, Lloyd,
Gavigan, Coddingham, and Williams.
 
A detachment of the Philadelphia detective police, force—Officers Taggert, George Smith, and Carlin, reporting to Colonel Baker—went in the direction of the North Pole; everybody is on the que vive for them.
 
To the provost-marshal of Baltimore, MacPhail, who knew the tone and bearing of the country throughout, was joined the zealous co-operation of Officer Lloyd, of Major O'Bierne's staff, who had a personal feeling against the secessionists of lower Maryland; they had once driven him away for his loyalty, and had reserved their hospitality for assassins.
 
Lieutenant Commander Gushing, I am informed, also rendered important services to the government in connection with the police operations. Volunteer detectives, such as Ex-Marshal Lewis and Angelis, were plentiful; it is probable that in the pitch of the excitement five hundred detective officers were in and around Washington city. At the same time the secret police of Richmond abandoned their ordinary business, and devoted themselves solely to this overshadowing offense.
 
No citizen, in these terrible days, knows what eyes were upon him as he talked and walked, nor how his stature and guise were keenly scanned by folks who passed him absent-faced, yet with his mental portrait carefully turned over, the while some invisible hand clutched a revolver, and held a life or death challenge upon his lips.
 
The military forces were commanded by Colonel Welles, of the Twenty sixth Michigan regiment, whose activity and zeal were amply sustained by Colonel Clendenning, of the Eighth Illinois cavalry, probably the finest body of horse in the service.
 
The first party to take the South Maryland road was dispatched by Major O'Bierne, and commanded by Lieutenant Lovett, of the Veteran Reserves. It consisted of twenty-five cavalry men, with detectives Cottingham, Lloyd, and Gavigan; these latter, with the lieutenant, kept well in advance. They made inquiries of a soothing and cautious character, but saw nothing suspicious until they arrived at Piscataway, where an unknown man, some distance ahead, observed them, and took to the woods. This was on Sunday night, forty hours after the murder.
 
Guided by Officer Lloyd, the little band dashed on, arriving at Bryantown on Tuesday. Here they arrested John Lloyd, of the hotel at Surrattsville, of whom they had previously inquired for the murderers, and he had said positively that he neither knew them nor had seen anybody whatever on the night of the crime. He was returning in a wagon, with his wife, whom he had ordered, the day before, to go on a visit to Allen's Fresh, The Monday afterward he started to bring her back. This woman, frightened at the arrest, acknowledged at once that in her husband's conduct there was some inexplicable mystery. He was taciturn and defiant as before, until confronted by some of his old union neighbors.
 
The few unionists of Prince George's and Charles counties, long persecuted and intimidated, now came forward and gave important testimony.
 
Among these was one Roby, a very fat and very zealous old gentleman, whose professions were as ample as his perspiration. He told the officers of the secret meetings for conspiracy's, sake at Lloyd's Hotel, and although a very John Gilpin on horseback, rode here and there to his great loss of wind and repose, fastening fire-coals upon the guilty or suspected.
 
Lloyd was turned over to Mr. Cottingham, who had established a jail at Robytown; that night his house was searched, and Booth's carbine found hidden in the wall. Three days afterward, Lloyd himself confessed—and his neck is quite nervous at this writing.
 
This little party, under the untiring Lovett, examined all the farm-houses below Washington resorting to many shrewd expedients, and taking note of the great swamps to the east of Port Tobacco; they reached Newport at last and fastened tacit guilt upon many residents.
 
Beyond Bryantown they overhauled the residence of Doctor Mudd and found Booth's boot. This was before Lloyd confessed, and was the first positive trace the officers had that they were really close upon the assassins.
 
I do not recall anything more wild and startling than this vague and dangerous exploration of a dimly known, hostile, and ignorant country. To these few detectives we owe much of the subsequent successful prosecution of the pursuit. They were the Hebrew spies.
 
By this time the country was filling up with soldiers, but previously a second memorable detective party went out under the personal command of Major O'Bierne. It consisted, besides that officer, of Lee, D'Angellia, Callahan, Hoey, Bostwick, Hanover, Bevins, and McHenry, and embarked at Washington on a steam-tug for Chappell's Point. Here a military station had long been established for the prevention of blockade and mail-running across the Potomao. It was commanded by Lieutenant Laverty, and garrisoned by sixty-five men. On Tuesday night, Major O'Bierne's party reached this place, and soon afterwards, a telegraph station was established here by an invaluable man to the expedition, Captain Beckwith, General Grant's chief cypher operator, who tapped the Point Lookout wire, and placed the War Department within a moment's reach of the theater of events.
 
Major O'Bierne's party started at once over the worst road in the world for Port Tobacco.
 
If any place in the world is utterly given over to depravity, it is Port Tobacco. From this town, by a sinuous creek, there is flat boat navigation to the Potomac, and across that river to Mattox's creek. Before the war Port Tobacco was the seat of a tobacco aristocracy and a haunt of negro traders. It passed very naturally into a rebel post for blockade-runners and a rebel post-office general. Gambling, corner fighting, and shooting matches were its lyceum education. Violence and ignorance had every suffrage in the town. Its people were smugglers, to all intents, and there was neither Bible nor geography to the whole region adjacent. Assassination was never very unpopular at Port Tobacco, and when its victim was a northern president i............