The wboli land forcÃ© placed at iho dispÃ¶fti of the President by the recent act of Congres is cstimated nt (ir,00U men, of wliich the rogÃ³la irmy vnll be 15 00C, and volunicers 5 ).)(!). ] is sniti that no requisiiions willbe made ai jnesant on any northern Irontier State. The Naval forco now tn Corhmisaion compria s 8.700 men: nnd the Presiden', is authÃ³nzci o incrensc the nuinber of vessels tj an Ã¨x'ten . that will require J5,000 or 20,00j men. Thut t!ic whole force at the disposal of ihe JPrÃ¨sf.Ãªn i c 'Ã¯h'ijthousnnl men. Tliis spretty wLll io hc very iirst movcment. In New Orlenns. it was fouiul impost!, Io i. raise the requisite amount of furces Air the ah 'I Gen. Taylor in senson, nnd recqurae was hot to drafiing. Dcserti.ins were also comnjion. Capt. BlandÃan! h had raÃ¯sed n cumpnnj f v)lunteers, found hinisclf desened by one lm! of them when on the point of deportare for ihc sent of war. Accounts from Mexico sta Ie that Gen. Parede. liad issued a nrolnniaiion commandjng the repelÃ ing of rtlÃ rnVÃ¡fding forcfee, and trenting il,,..-,, ar enemies, and announcing that ''defensie irnr' will beprosecuted in all points of the Moiicui territory. The removal of tlie U, S. urmy u he Rio Grande he considera an invasiÃ³n ol tin Vfezican terriiory. The papers of variÃ³os sections concur in reesDiuing that the adtninisiraiion has deterniinet â n an invasiÃ³n of Mexico, ui takeefTect in Au juef, under the command of Gen. Scott. Tlu main army will advance from Mutampras ini. Mexico, while n divisiÃ³n of 4,('OO men wil sirike for Chihunhua, and a third divisiÃ³n wil 'ntlvance io Santa Fe. Total force, 2: llegi nients: 4,575 horsc: foot, J5.::6!: in all, abJii â 0.000 men. From the Free Press E.vlra of Saturday. GREAT BATTLE. The New York ITcrald of Tuesdav morning, nnnounces the arrival at New Orleans of the slenmcr Florida. Capt. VV hartÃ³n, of the U. S. A. benrer of despa lelies, arrÃ¯ved on the first iust. The main body of the army of occupalion marched from the camp on the Rio Grande, Jeaving in the garrison for field operations the 7th regiment of infantry. and the company of field nrtillery coramanded by L. Lowd, and LiÃªulennht Briggs, ihe whole comnianded by Major Brown of the infantry. On the 2d inst. the army encamped at Point Isabel early in the morning. At 5 o'clock on the morning of the 3d a fiie was opened on the fort from one of the Mexican batteries and wascontinupd with 7 guns. The fire was immediately relurned, and the battcry was silenccd by our guns in 30 minutes. Two of the enemy's guns were supposed to be dismounted. A brisk fire of shot and shel] was kppt up, but without damage. A delibÃ©rate fire was kept up by our 18 pounders upon the enomy's guns in the city of Motamoras. The fire of the enemy was kept up until half past 7. At 10 they ternporarily suspended. Tt recommonced and continued at interval -, until 12 o'clock that night, although it is believed that from 12 to J600 shot.s were fired bv tiie enemv. Not one of our jjuns were dismounted tljough the enemy's fire was for some time, concentrated on the 18 poÃ¼nder litteries, and the shot frequently struck the emb rasure?. Al 5 o'clock on the 4th the firing was commenced by the enemy, which was centinued for 12 or 15 shots, and kopt up at long intervals during the day, but vii hout effect. Our boys dismounted one of their 18 pounders and threw it 50 feet in the air. The following addilionnl particular? are galhered from N. Ã¼rleans papers. Il is impossible lo describo the enihusiasm with which ihe news was received at New Orleons.J lie popuiaiion appearcd to be suddenly quadrupled. Joy, it is said, was depicted on every countenance. By the arrival of the stearr.er N. York Cnpt. Philips, from the Brazos St. Jago, via Galvrston, the report is fully confirmed of the Moxicans having thrown themsehes in force beiween the Ameri can camp and Point Isabel. Capt. Walker, of the Texan Rnnger?, who it will be recollectcd gallantly oflbred !o carry communicutions from Poini Isabel to Gen. Taylor, succeeded in hs desperate enterprise. Gen. Taylor, immediately on being made acquainted wiih the condition oÃ aÃTairs, deterniined, with a part of his arrny to march to Point Isabel, and accordingly, on the evening of the lst inst., left hiscitrenchments wiih from a thousand lo twelve hundred trien, cavalry, artillory, and infantry. He arrived at Point Isabel on the morning of the 2d, without having encountered a single IVfexican. On' the morning- of the 3d, having heard the firing of artiÃ¼ery in the direction of Metamoras, Capt. Walker was again despatchcd to immedialely ascertain the cause. Thia brave man ogain succeeded in renching the camp, and on his return on the 5ih, renortÃ¨d that the Mexicans finding Gen. Taylor absrnt from the camp. and liis forces divided, took the opportu nity to open their battcry at Mefamoras on the camp, and those on the castern side of the Rio Grande, at the same time marie an atlack in the rear. But onc American was killed, and none woundod. Wliat nprabec of the enemy was killed or wounded is not known to any degree of eertainty. It is reported [hal as many as 700 were killed, and that a suÃficient number of houses uere not left standing in Alalamoras to ailbrd shelter to the wounded. The ultÃmale resulÃ is yct to be known, however, and the firing was oontinued at intervals up to tlie lime of the departure r)f the New York from the Brazos, on the 6th, about 1, P. M. Gen. Taylor was preparing to return Dn that day wiih supplies. He expected o be attacked on liis march, and was fulyprepared lo meet the enemy. It was supposed he would tako with , lim the regula rs sent clown by the New fork, all of whom were landcd in safey on the morning of the Gth. As to the number of Mexicans on ; her side of the Rio Grande, it is still, in t great mensure, matter of conjecturc. ( riiose on this side of RÃo Grande have Iready been estimated at 3000, and t is r robribly they would not cross with a much smaller forcÃ©. They are iiuw es,1 limated ot 5,000 ! The Dumberon botli skins of the river ,, are eslimaied by nono at Ã©ea ili;m 10,000, t md by many it is believed lo bo as high as lfi.OOO or 20,000. When Ge. Ta y lor left Polnl I-abel, . to reiurn to ihe outromched camp, oppo, silo MaJarnorui, ihere vvÃ±s uot the leaM doubt tint bc VVnuld br Ibrecd to cut his ' v;iv to his entrenchmenis (hrough the viiMly supeiior miinhcrs of the enemy, wlio were known to be po.stod in largo l'.Mvs among the altnost nipassibhc ihieket ot chappernl un jhe rond wilh a " dotcrminalion to cut liim o(f, it" lossible. 1 in liis ntteinpt to regain his ot her forces. l! All accounts ugcee lint tho Mexica furecsare rapidly Uocking in from al 5 qunilers. I Gen. Tnylor amicipated a formidable c desperate oppoqitjon to his maren; bul de lermined to uccomplish it, or periÃ¡hi 1 â - seems lliere vvas ever.y reason to suppos â and to expect opposition to bis march b the deepest anxiety is feit tbr the result We have tbc N. O. Picayune of lli L, 12th inst.,in which we find the followin letter from un oÃlicor at Point Isabel containing wbat appenrs lo be a more au ' thentic account of the battle (han thos previously publUhcd : Point Isabel, May 5, 1S10. Gknti.t.mkn : - VYhen i!m exprÃ©s ! carne in this morning, 1 hurricdly pen II cÃ¼led down the gratifying intelligenc which it b'rÃ³ugbt us, exjiecting -ihe U; i would leave in a few minute?. It no only waits for Gen. Taylor's official dis patch, which is being prepare.-] for Wasli ington. Ilaving heard the officia] repoi from Major Brown read, and huving f letter before me frobi tbere, I will giv f yon fartlier parliculars accordingly. On the morning of the 3!, at reveille - the MÃ¨xicaris oponed f.heir batleries upot 3 the work, throwing balls and sbells with i out intermission tÃ¯nill sunset, finishing 5 wilh half a dozen extra ones at tatiuo fo a lullaby. , At reveille on ihe 4lh ihcy oponed a - gnin, sending a few shots and shells l which compliment was ropcaled at noon r Our arlillery silÃ©riced the fort oppÃ³sil , ours in half an hour after the firing com r menced on the 4th, and knocked thre embrasures into onc. ) Thiri Cftused tbem to stop firing thor i for a considerable time, lo ropair dama . ges. Our aitillery alsn dismounted sev . eral of thcir guns, and from appearance . must have killed many men. On ou Ã1 part but one sergeant, of the 7th infan i try, was kilied - beii-g shot in the heai with a 3 Ib bal}. Ne was carried o the hospital, when, strange to say, a shel feil and blew the remainder of his head olF Some 20 men were standing arounc the hospital when iheshe.ll burst ; sever nl were knocked clown, but none injured One artÃ¼lery soldier wnssljghtly wound ed by a piece of a sheilj and many have made narrow escapes. We onlv k?p up our fire for aboul two hours - sÃ¼vins our ammunition wbilst thcirs was being thrown away. From their having thrown from 1500 to 2000 shots and shÃ¨lja, and kilÃ¼ng bu one of our men and wounding .anoiber. yo'j may judge they are none of the best artillerists, and lhut we had good defences. Their shots rendered rt good many of our tents unsÃ©rviceable, but all ommen are in good spirits and anxious to come to close quarter?. Our piquet guard is now firing at a party of Moxiean soldiers, ahout a mile below tlie fort. The Cliapparal betweeu lins and the fort is like a bee-hive, so full is it with Mexicans. It is thought Ihey will makean nssault on the rear of Hufort, and try nnd ropel tl)e march of the troops from this place roturning. Gen. T. leaves as soon as a rÃ«infÃ³rcÃ«rneht ar rives here, wliicb will enabl'Ã the work to be defended without the force which he brougbt down from above. In baste, yours, S. S. F. 77he Picnyunc is informed thnt il was understood to be Gen. Taylor's intention to remain at Point Isabel iÃ¯ntil that post should be perfectly fortified and a largo accession of troops should arrive. The reader will be delighted to hear that neiiher Cnpt. Thornton nor Lieiu. Kaue were killed in theaflairof the surprise of Cupt. Thornton's dragoons. Voi.u.vtiokks - We notice that 2000 picked warriors of tho Creek natiun ol Indiana, have voluntcered their service? to the Unitod States in their contest w'vh Mexico. The namber of volunteers callÃ©d for ft om the Slatos of Tennessee, Alabnma, Missouri, Mississippi, Louisiana, and Texas, amounts to about 15000. Tnoops. - The Secrctary of War ha? made a rrqtiisition upon the Governor o1 Michigan for one regiment of volup.tcer nfantry. The regiment to consi-t of ten companies of 64 men each. They are r.ot to march immediatt-ly to the seat of war, but :o hold themst-Ives in readiness whenever their services may bo requirod. The Freo Press says : " the Frontier Guards have anticipated the requisition b tendering their services to the President."LArTERr! VAR ON THÃ RIO GRANDE. Bij Mctgnelic Tclrgraph. 1,200 Mexicans Rkpohthd Killed ! Mcxican Army Tic ice Iiouted ! ! DEATM OF MAJOR RlNGOLDÃ¼! General Vega Captured ! ! ! ! The American Army Trhimplianl ! ! ! ! ! We are indobled, says the New York Herald, to Mr. Enoch, of the Naliona! Gazoite, for the foÃ¼owing higlily imporlant intfiÃ¼igence. It was conveycd from Mobile to MonÃgomcry by expresa, ahead jf iho mail, and from Washington by Telegrapli. it nppoars by llie New Orleaus Pica,-tine of ihe I6th, nnd Mobile Herald of hc I81I), that thero has been two tromend'us ergngemonls botween the American nd Mexican iroops, in which the latler lost 200 men. The first occurred on the 7th, â as Gen. Taylor was returning to hÃs cÃ¼mp oÃF Matamoras from PoÃnt Isabel with sixteen hundred metÃ ; opposed to hiin vvere frÃ³ni 5 lo 7,000 Mexicana. Tlie ÃMt.'xicans weio rephlÃ¡ed ut the poini oÃ' the bayonct. The American army slept on the field of biutloono uiglit, and on the next day 200 Mexicana wÃ©re found dead, and severnl piceos of Mexican artillery wcre capiured by onr forces. '1 lic most rnelancholy port of the batllo is the reported dealh ol' the brave M;ijor Ringold. The Mexican General Vega, the onc thnt had thÃ© interview wiih Gen. Worlh on th; left bank of the Rio Grande, has been taki'ii priioner. The hecond bat' Ie look place on the 9th. cornmencing al 3 P. M. within thrce miles of (Ã¯en. Taylor'.s camp. The action as in the edge of a ravine, and one mile from llio vÃ¡v oÃ" a cliappaial twe'.ve miles in width. The Muxicans comnienccd the action with ihc-ir artillery, which wns posted po as io sweopa nnrrow ;pas80gQ ihrough which Gen. Ta) lor was advancing.