Speculative Moohology. MESSRS. EDITORS :—The idea that. thl) full moon is hot seems to me so unscientific, that, tlj,0v.gh advanced or advocated by all the Herschels and backed by the Rosse reflector to boot, I take the liberty of offering a reason or two which may go to prove it untenable. The convexity of the moon's surface is so much greater than that of the earth, that the moon must be effected bv the sun's heat less than the earth is by a proportion considerably less than the ratio of size or diameter between the earth and moon would seem to indicate—nearly all the heat being deflected or reflected into space and dissipated. (And this convexity is possibly the cause of so little heat being reflected directly earthward.) The sun's rays can have but a small spot—small, as compared with the earth in this respect—on which they can at any time be said to fall vertically; a much less distance being required there than on the earth to reduce them to rays falling through all degrees of obliquity down to horizontal. So the vertical and nearly vertical rays may move around the moon quite - slowly, and yet heat but at most a tropical belt, while there would be temperate and frigid zones as on the earth. But it would be doubtful whether that belt could by any possibility reach a temperature of 492° as claimed by modern astronomers, All this, supposing the moon has all the conditions and' requirements which the earth possesses for rendering sensible the solar heat; but the first and principal one of these is an atmosphere and astronomers tell us the moon has none at all; and without the atmospheric lens to contract the sun's rays together and squeeze out the heat; how, and from whence is free caloric to be obtained ? On the earth it is known that at a certain hight, where (and because) the air has but little density, snow never melts, even under the tropics ; whence we may infer that at greater elevations and with l)jr still more rarefied, ice and snow would remain unmeltt;d even if exposed to the rays of an equatorial sup for a century_and with no at, mosphere at all it would be fitill colder than with a little. It i!l stated that the additi<j!t of a small per centum of a denser gajj (carbooic aoid) tq pur at-masphere or iacreased © 1869 SCIENTIFIC AMERICAN, INC 342 density due to a few n;.ileg more in hight or depth of the airman would—unlef;fg eo»ected by increased evaporation-C'1.use the earth to grow hotter and hotter, so as to finally preclude the possibility ot human existenoe; or it would enable the earth to W.ain its heat indefinitely long, though the Bun should go into the comet busine^, I'!peed away, and leave us out h^ere in the cold of the planetary spaees. All depending on atmosphere : now if the moon has Ho atmosphere, I don't quite see how it can form an exception to what we are bound to consider universal laws, operating always in the same manner—^^dltions being the same— whether on the earth, mooft, sun, or stars. So, unless the moon is formed of Materials new to science, or unless it has an equivalent to our atmosphere in some form (a fact which we may not be able either to prove or disprove Oil ttCMuht of there not; being moisture enough to foMtt eiouds, fogs or mists), I mullt continue to think the MOto does not reach a tempera- tuJ;! of 492°—or any other number of positive degrees,— “ during its long lunar day of 300 hours." Another thing: give the moon an ataosph%re iike ours, and as deep, (a larger portion than is entitled to) yet, at- itraction is so much weaker thefS than on the earth that the :air would expand into space, and I opine the density of that atmosphere would be lesi! at the moon's surface than ours is at the tops of our highest mountains. Consequently, clouds could not float in it, nor birds fly in it, nor ordinary vegetable or animal life have any existence there. All water, if the moon had ltny, would be congealed, and there would be but little motion, or chemical action. Intense cold would always prevail, a nd snow or ice would never melt under a perpetually verticil sun—if such a thing could be had for the occasion. WUmmgton, Del.W. L. DAVIS. 'To Plow Manufacturers. "MESSRS. EDITORS :—By inserting this article in your valuable jJI'^per, it may subserve the interest of the Northern mechanic and Southern farmers. What the South mostly needs is manufacturers, and at present the greatest needed, is a plow and agricultural implement factory. The necessity for improved plows, harrows, etc., are being felt, and the use of lIuch would greatly increase were they manufactured among us, but so long as imported from the North, the cost of transportation and commissions put them out of our reach. As one instance, I will mention a case in point. I saw on a gentleman's farm two turning plows (ron beams) made at Hudson, 3ST. ¥., which cost at the $8 a piece. He told me that the freight on those plows from that shop to Rome, Ga., was $28, making each plow cost $32, and such is a fair representation of the cost of all the plows received, and seven tenths of them are worthless articles imposed upon us. Here is another instance. I showed a farmer from New Jersey a plow manufactured at Ixraisville, Ky., a one-horse turning plow—cost, delivered at at Rome, $10. He said such a plow would not bring ten cents in their State to use on their farms. The cases recited above show how we are imposed on, and our only remedy is in hpving factories at the South. We have iron, coal, wood, and water power in abundance mear Rome, Ga.. and a more eligible point cannot be found ;;mywhere South to put up such an establishment, the climate, water, society, etc., all that dould be desired. If there are any plow manufacturers North desirous of establishing a factory South, they would do well to come and see for themselves, and if they would call on me at my farm, two miles of Cave Spring and fourteen west of Rome, it would afford me great pleasure to give them all the information they may need as to the advantages of setting up such a factory in this part of the country.JNO. H. DENT. Cottage Home, Ga. Aero-Steam Generators. MESSRS. EDITORS :—In No. 13, current volume, of the SCIENTIFIC AMERICAN, you published a description of Mr. War- sop's aero-steam generator, and an account of his experiments. Mr. Warsop is in error in his way of accounting for his gain of power. He attributes it to the expansion of the air which he forces into his boiler. This is not the case, as air becomes heated by compression, to a higher degree than the steam itself, whenever it is forced into a boiler, carrying a pressure of sixty pounds or more to the inch. This heating is done by mechanical force taken directly from the engine. So there will be but little heat taken from the fuel by the air ; and, consequently, very little expansion results from this source. The specific heat of steam is greater than that of air, and gases expand equally under the same degree of heat ; so in forming an equilibrium of heat between the air and steam, the air being heated to the greatest degree, there will be , more contraction of the air than expansion of the steam, volume for volume. That he gains all he claims, I have no doubt at all, but he is not aware of the true source of gain. Were it not for this heating of air by compression, air-engines would be a success; as it is, they can never be of any great valUe for converting heat into motion ; neither can air ever be employed as a medium for transmitting power to long distances, as all this heat resulting from compression will be lost by radiation. The true source of gain in Mr. Warsop's apparatus is this: All water contains a large quantity of air in a state of solution ; this air occupies the inter-molecular spaces of the water, and forms an elastic cushion, which forces the molecules of water apart, oihus decreasing their cohesion. Air will prevent water trom absorbing- any other gas, which it will do when it contains no air. Air alw has the power to expel other gases in a remarkable degree ; consequently, it will prevent water from absorbing its own vapor, and will expel it as fast as formed. Water contained ja stem Joilerlj (joI),ta,me scarcely !\Iny air; because it is in compressible, while air is- very elastic ; water always absorbs the same volume of air without regard to pressure, but when it is folied into a steam boiler under a pressure of 100 pounds to the iachj the air contained in the water is compresed into about one fifth its original volume, thus leaving a vacuum of four fifths, besides air is expelled hy heat. When water does not dOlitaih iti Complement of air, its eohesion is 'Vastly increased by the absorption of its own vapor, which fills its inter-molecular spaces to such a degree that it restores the attraction of cohesion between the molecules of steam and the molecules of water to a great extent; cohesion not being annihilated by heat but only overcome. When air is absorbed by water there ig no attraction of cohesion between the molecules of 'Watel' and the atoms of air, but a positive repulsion, which widens the distance between the molecules of water, thus decreasing their attraction, thereby facilitating the molecular motion of heat. Also in Mr. Warsop's apparatus WA have liedEy a perfect circulation of the water ; which is attained in no other boiler. After a study of the subject for a number of years, I am satisfied that the above are facts. In 1866, I obtained a patent, through the Scientific American Patent Agency, for a steam generator similar in principle in every respect to Mr. Warsop's apparatus. D. B. TANGER . Bellefontaine. Ohjoj Tile Fossil Man Of Onond.aga. MESBEB. EDITORS ;—AS an old subscriber (I have the SCIENTIFIC AMERICAN from its first No. to the last one), and as an adm$er of the great truthfulness, candor, and intelligence which have always Bharafiterized your opinions and expressions^ Mg leave to call your attention to an article on page 310, tlurrent volume, upon “ The Fossil Man of Onondaga.” The writer, “G. B.,” who dates his communicatibn “ Syracuse, N. Y.,” not only makes a general attack upon all connected with the Onondaga Stone Giant, but seeks to palm off both upon you and upon your readers, the infamous and ridiculous Geraud hoax—which was concocted by a physician, in this city, purely “as a hoax and as a test of the credulity of New York editors,” and, as the author now says, without the least faith that any one would believe it — as an explanation of this most marvelous .wonder of the age. The only theory which gained the least credence in this vicinity, is embodied in what is known as “the Tully story.” This story relates, that about one year ago. a “ four- horse team “ passed through Tully, which is some six or seven miles south of Cardiff, drawing a large box, which was evidently heavy,and that the team was in some way connected with one Geo. Hull, of Binghamton, whose conduct was observed to be mysterious, and who was a cousin of the man Newell, on whose farm the Giant was found, I cannot undertake, in detail, to refute this,at first, apparently possHAe theory to account for the discovery of this Giant Statue, or “ Stone Giant.” In addition to the affidavits I herewith send you, and which cover this entire ground, I will simply say, that any theory involving the idea that a stone statue, weighing 2990 pounds, was brought in an ordinary wagon, from nobody knows where, and deposited some three or four feet below the surface, and partially under a large limb of a tree, by two men, is so entirely ridiculous, that no sensible man, who is in the least acquainted with the surroundings, can possibly give it a second thought, and any belief, either in this, or the crazy Canadian or Geraud story,requires a stretch of credulity far greater than that necessary to regard it i very ancient statue, or even a petrified Giant. Its removal required about fifteen selected men, with the most nicely adjusted machinery and appliances, and the whole, wagon, box, and sand into which it was embedded for safety of transportation, weighed 7965 pounds, or almost four tuns. It would, after stating the above facts, be not only a waste of words, but an insult to your good sense, to spend more time in this communication, to disprove either of the silly theories above alluded to, to account for this strange image. I hardly need state, as it is already a matter of such public notoriety, that the State authorities have undertaken the investigation, sending here the Regents of the University, together with the State Geologist, Prof. James Hall. While these gentlemen have not (so far as we know) been enabled to come to any definite conclusion as to its origin or exact antiquity, they have settled several questions which are of great importance, as connected with this subject. The composition of the Giant is declared to be sulphate of lime or gypsum. On the supposition that it is hewn from a rock, where did it come from ? Could it have been made here, or hereabouts ? Prof. Hall, after a most careful examination of all of the gypsum quarries or beds in this county (and there are none near elsewhere), has decided that no gypsum, either in kind or quality,exists in this region, from which this stone Giant could, by any possibility have been taken. If, then, his Giantship be a carving,or the production of the artist's chisel, he is a foreigner. This is further shown by the fact, that from first to last, there is not the least shadoJV of evidence tending to show that the work was done anywhere near where he was found. The figure is wholly unique in design, and in the surface left in every part of the body and limbs where they are not corroded by water. The fi^re is that of a male, entirely nude, with every part fuliy shown, but without any attempt at representing hair or whiskers. It is made, neither to stand up or lie down, having neither pedestal or tablet accompanying it. It is carved(?) as perfectly upon the back as upon the front side, and was found lying upon a clay bed, which underlies the surface of the whole valley,which is alluvial and, vegetable mold, to a depth varying from one to' five feet throughout the valley. It was found lying upon its back, almost exactly horizontal, and in the direction corresponding to that of the stream, as it is supposed to have ron [NOVEMBER 27, 1869. at some former period. On its removal there was no trace of anything whatever to indicate its origin. The statue(?) is most imposing and impressive. It has nov been seen by not less than twelve thousand persons, includ ing many of the most scientific men of the nation, and, so> far as I am informed, or have had the means of knowing, not a single individual has ever examined it who was not impressed with the feeling and belief that it is the most extraordinary and gigantic wonder ever presented to the eye of man. Be it what it may, it presents a most perfect human form, of colossal size, defying the present state of science, whether geology or archreology. Its origin, we have to confess, is as deep a mystery as' when first brought to light. Any theory,traced but a Jew steps, involves a belief in hitherto unproven facts or assumptions having, mainly imaginary foundations. Had it ever been well established that the human body was capable of becoming petrified so as to preserve the entirety of every part, it would be far easier to suppose this a veritable petrifaction of one of the Giants that lived “ in those days,” than to suppose it a statue. But the negative of this having been assumed, and all subsequent reasoning and facts, made to square to the assumption, that the petrification of the human body was impossible, the statue theory is, of course, the only thing left, and the conclusion is, that it is a statue, because it cannot be a petrifaction. Whether this is, or is not, good logic, in the present state of knowledge upon this subject, I am not now disposed to offer an opinion, but will merely add, in this connection, that we have, really, no fewer obstacles to overcome, in concluding it a statue. There is not a chisel mark upon the entire image, nor of any other implement employed by human hand. The style of model, its perfection, its peculiarly smooth surface, all defy the artist. Be it statue or petrifaction, it has every indication of having occupied its late bed for a great number of ages, and was not, as your correspondent asserts, gotten up to impose upon “a gullible public.” It is now “ lying in state “ in this city, where, for some time, all who are disposed to examine its form will have ample opportunity to do so ; ;and I would add, in all due deference to your all-wise correspondent, that men of sense and wealth have thought it a reality of sufficient magnitude to make it an objest to pay a large sum of money to possess it. A. WESTCOTT, A.M., M.D. Syracuse, N. Y. The Stone Giant. , MESSRS. EDITORS :—Upon reading the several communications in your paper, I judge there are two disputed questions in relation to the stone giant, recently exhumed at Cardiff. 1st. As to its being a fossil. 2d. As to its antiquity . • On page 43, vol. I., of Clark's “History of Onondaga,” published 1849, is recorded the fact that there existed among the Onondaga Indians a tradition that among the things that heretofore had been- troublesome to their nation were the “ Quis Quis, or big hog, the big bear, the homed water serpent, and the stone giant.” The author seems to have thought the tradition not well founded, as can be seen by reading the work (which I have not at hand or I would quote further). They have found the stone giant, and no doubt the hog, bear, and serpent are there. Perhaps if' the Onondagians could read their own history there would be less of a pow wow over their recent discovery.C. ALVORD. Washington, D. C. Cultivation of the Poppy in Texas. MESSRS. EDITORS :—In a former number of your paper, I noticed an article on the culture (i)f the poppy, written by my brother, James Byars. He mentions seeing the white poppy growing wild and in great abundance about West Liberty. This is the Argemone Mexicana, or prickly poppy. The whole plant abounds in a milky, viscid juice, which becomes yellow on exposure to the air. This juice, which is acrid, has been used internally in obstinate cutaneous eruptions, and as a local application to warts, etc. The flowers are said by De Can- dolle to have been employed as a soporific. The seeds, which are small, round, black, and rough, m doses of two drachms to a pint of watery infusion, act as an emetic. In smaller doses they are purgative. An oil may be obtained from them by expression, wbich is equal, if not superior to castor oil in mildness and certainty of action. The oil might be m^de here in any quantity from the abundant wild growth of the plant. There is no doubt, I think, of the adaptability of the soil and climate here for the culture of the white poppy (Papaver somniferum), and if you can send the seed or inform me where to procure it, I will give it a trial.WM. M. BYARS, M. D. Columbus, Texas. Supply of Water in Large Cities. MESSRS. EDITORS :—1 would like, through the medium of your very able and valuable journal, to make some suggestions relative to the supply of water in large cities in cases of fire, and others of importance to those using steam boilei's, etc. It is well known that immense amounts of money are 1of:jt annually by fire which might be saved provided there was some means by which water could be obtained at a few minutes' notice instead: of being compelled (as is the case in many instances) to await the arrival of fire apparatus. The latter alternative has to my certain knowledge resulted several times in severe losses, which, had the case befiln otherwise, would have only been a trifling loss. I would suggest placing at the supplying reservoir large pumping engines, supplied with safety-pressure valves, and © 1869 SCIENTIFIC AMERICAN, INC NOVEMBER 27, 1869.] instead of allowing the water to flo” by its own gravitation, to force it through the pipes under pressure, of sufficient stength to throw water at any desired hight or distance, and by placing hydrants at various points throughout the city (the more the better), with 4, 6, or 8 discharge openings, and establishing hose houses near by, an immediate and abundant supply of water could be obtained at any time, thus making a saving of millions of dollars worth of property annually. It would furthermore be a means of feeding steam boilers without the necessity of using steam pumps. I should think that a large portion of the water now wasted might be saved, as the above arrangement would necessarily involve the passage of laws, levying a heavy fine upon any one allowing the water to run when not in actual use, and would also compel the abandonment of lead pipes, which could not stand the pressure, and which are the sole cause of much sickness in large cities on account of their poisonous action on water. It would compel the use of pipes of different metal, and thus be the means of saving many valuable lives. I should think that this arrangement could be carried out without much. expense, compared with the expense of the present fire department, and in the end allay all fears of a scarcity of water, which is now caused by the immense waste through carelessness and otherwise. Mobile, Ala.C^^ES S. BAILEY. [Some of our practical correspondents will be able to point out grave impracticabilities in this scheme.—EDS.