Iron Used as a Monej Medium. To the Editor of the SCIENTIFIC AMERICAN: I am a constant reader of the SCIENTIFIC AMERICAN, though not a regular subscriber, on account of the fact that 1 can get the paper at an earlier date from the news stand than if sent to me direct. In your issue of April 22 1 have read with interest an article by Prof. Alex. Del Mar, entitled, "Our Heritage of the Mechanical Arts." In giving the history of iron, its scarcity, usage, etc., the writer among other things says: "Both iron and steel were certainly very scarce in the West at the periods mentioned. Homer, tenth century, mentions poleaxes, shipwright's tools, plow shares, sheep hooks, and chariot wheels in the Troad; yet in Lacedmonia, in the time of Lycurgus, ninth century, iron was still so valuable that he employed it as a material for money." The writer seems to emphasize the point that Lycurgus used iron for money on account of its scarcity and value. It is true that Lycurgus did use iron for money, but not on account of its scarcity or value. On the contrary, he made use of iron for money to aid him in his new system, by which he wished to destroy the avarice of his people. Plutarch says: "Not content with this [the equal division of the lands, etc., of the Lacedmonians] he [Lycurgus]' resolved to make a division of their mov-r ables too, that there might be no odious distinction or inequality left among them; but flnding that it would be very dangerous to go about it openly, he took another course, and defeated their avarice by the following stratagem: he commanded that all gold and silver coin should be called in, and that only a certain kind of money made of iron should be current. A great weight and quantity was of very little worth; so that to lay up twenty or thirty pounds, there was required a pretty large closet, and to remove it, nothing less than a yoke of oxen. With the diffusion of this money, at once a number of vices were banished from Lacedrjonia; for who would rob another of such a coin? Who would unjustly detain or take by force, or accept as a bribe, a thing which was not easy to hide nor a credit to have, nor indeed of any use to cut in pieces? For when it was just red hot, they quenched it in vinegar, by that means spoiling it, and made it almost incapable of being worked." Clare in his "Universal History of the Wortd," vol. ii., page 585, says: "To render the state dependent only on its own territorial products, and to prevent any individual from accumulating an undue amount of wealth, he [Lycurgus] prohibited the use of any money except an iron coin, with so small a value in comparison with its bulk and weight, that the necessity of using it as a medium of exchange would make it difficult to carry on trade, especially foreign commerce. By subjecting this iron coin to a process rendering it brittle and unflt for a [an] other use, Lycurgus endeavored to destroy every desire to hoard it as a treasure." Rellin, in his "Ancient History,"vol. i., page 687, says: "First he [Lycurgus] cried down all gold and silver money, and ordained that no other should be current than that of iron, which he made so very heavy, and flxed at so low a rate, that a cart and two oxen were necessary to carry home a sum of ten min [Ave hundred French livres, about $88.80] and a whole chamber to keep it in." This was done for the purpose of sapping the foundation of avarice. From the above quotations, it would seem that while iron was much more valuable than it is now, still it was not so valuable as to justify its being coined into money. It seems that a team of oxen could haul about $88 worth of iron. I presume the same sort of team might haul one-flfth of that value of iron at the present date. As stated, the idea conveyed by Prof. Del Mar in his article seems to be that iron was so scarce as to justify its coinage into money. I do not think that history will bear out this statement. I do not know whether you care to have letters of criticism of this sort or not, but at any rate, venture to give you the facts as stated by ancient historians. Lt. M. NEBLETT. Fort Worth, Texas, May 25, 1905. News comes to us from the Harvard Observatory at Arequipa, Peru, that Eros has been photographed there with the Bruce telescope. Eros, be it remembered, is the nearest of all the heavenly bodies, with the exception of the moon.