A letter from Rome, published in the Paris _Debats_ states that another attempt to murder by means of an explosive contrivance, had occurred there within the last few days. A tube, filled with gunpowder and bits of iron, had been placed in a passage leading to the laboratory of a chemist, at whose shop several persons, well-known for their attachment to the Pontifical Government, usually meet in the early part of the evening. Fortunately the match fell out of the tube, after having been lighted, and the explosion did not take place. The police had not discovered the culprit. The same letter mentions a new difficulty that has lately arisen between the French and Papal authorities at Civita Vecchia. The new French packets of the Messageries having superseded the old _bateaux-postes_, it appears that the captain of one of the former, claimed for his ship the privileges of a vessel of war, a claim which the sanitary authorities of Civita Vecchia would not admit; whereupon Colonel de la Mare, commandant of the garrison of Civita Vecchia, had two or three of the _employés_ of the Board of Health arrested. It was believed, however, that the question will be amicably settled. In SPAIN public attention has been almost entirely absorbed in the Cuban question. The Spanish papers were very violent against the United States, and clamored loudly for war, though the necessity of European aid in such a contest is very sensibly felt. It is announced with every appearance of truth, that England and France have entered into engagements with Spain for the purpose of preventing future attempts upon Cuba from the United States. To what extent this guarantee goes we have no precise information; but it is stated in the Paris journals that a French steamer has been dispatched to the United States for the express purpose of making representations to our government upon the subject. Spain has sent reinforcements to her army in Cuba and is taking active steps to increase her naval strength for an anticipated collision with the United States. The usual party struggles agitate the Spanish Capital. It is said that the Government contemplate decided reforms in the Tariff regulations of the country, maintaining the protective duties wherever Spanish manufactures can be aided thereby, and encouraging competition in all those branches which have been stationary hitherto. TURKEY.