The New York Times contains an altitle on the above subject in which it is suggested that puddled steel be employed as a substitute for wrought iron in boilers. a In order to meet obj ections to i ts use it ridicules the experim ent which was lately made in England with steel beilers on board of the s teamer John Penn, from which, on acconnt of a leak, they were removed aft er a very brief use and replaced with iron ones of the usual construction . So far "0 it relates to strength, which is a m ost important feature, puddled steel is at least one-third stronger than wrought iron, and boilers made of it would certainly be, i n our opinion, proportionably more 8afe from explosious in all cases whatever. The writer in the Times, whom we think we know, is an engineer of repntation, and he states that the steel boilers of the Jolm Penn were in all likelihood very imperfect in their construction, adducing in support of his conclusions, that steel has been e m ployed successfully for fire-boxes on the Scottish C e n tral Railroad during the past four years, and in such situations it is more severely tried than in marine boilers. We hope further experiments will be made with steel in constructing boilers. The Motion of Rifle Bullets. -The subject of rifle can non is attracting a great deal of attention in England, and the thorough discussion that it is receiving receiving is bringing out many ideas of interest. Among others, we find this : When an elongated missile is discharged from a rifled canqon at a considerable elevation in order to obtain a long range, the rotation of the bolt causes its axis to continue parallel to the liue in which it leaves the cannon, and hence i t will not strike the target with its axis perpendicnlarly to the face of the target, but inclined at the same angle to the target that the gun has at the time of its discharge. The L?ndol En.qineer suggests that as the rifling of guns is only an expedient to counteract the effects of imperfec tions in either the gun or the shot, these may yet be made so perfect by improved maehinery as to dispense with the necessity of rifling altog?ther. Peculiar Sheep.-In the Punjaub, India, there is a breed of sheep so small that a full-grown one is not larger than one of our lambs of about four weeks old. These creatures have small bones, a full fleshy carcass, and the mutton is excellent. Each ewe has two lambs per annum and yields about three pounds of fine wool This sheep would be excellent for our country, an d some spirited stock raiser IOhould import a flock of them . The habits of the sheep are as dom esticated as he dog ; it feeds on every kind of vegetable, grain, and fruit, and takes crumbs and fruit parings from the hands of its master. The country which this sheep inhabits has a climate similar in tcmperat1:re to that of the United States. ----------. ploy Waves of Fire.-A traveler in the Sandwich Islands, while visiting the volcano near Hilo, witnessed a wonderful phenomenon. As he was sitting at heat, startled by a noise like the rushing together of vast bodies of water, and was obliged to run to escape the great heat. The whole surface of the lake was in the wildest commotion, wave dashing on wave. Great billows ot fire rolled from every side of the lake, meeting the fierce conflict, r ecedin g and rush ing toge ther agai n with increased fo rc e, shooti ng into the air, pe rhaps a hundred feet, a vast spiral body of red liquid lava, which finally combed over and fell in graceful spray back into the lake again. When the lake was restored to its us ual order, it seemed to have fallen at least ten feet. ploy Notice to Assignees of Patents.-We have in our possession over one hundred assignments belonging to persons and firms residing in this city an d Brooklyn , which have been returned to us from th e record department of th? Patent Office. Assignees who h ave deposited their deeds with ns for recording, will please call or send to this office an d receive th 'm. BLACK vulcanite is composed of india-rubber kneaded with sulphur and graphite, then subjected to the action of high presaw:e steam in a dose chamber.