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!% in., and J in., giving powers of 5, 7J-, 10, 15,20, 30, and 40 diameters. The writer has applied the same names to his oculars, applying the intermediate fractions THa in.. Jin., and Jin., to intermediate powers; and he is satisfied, by experience of its convenience, that this nomenclature only needs a trial, to secure its adoption by all who use the microscope for other purposes than amusement. Of course any microscopist, having determined the power of an objective and the powers of the microscope when that objective is used with his various oculars, can obtain the powers of his oculars by dividing the latter numbers by the one first named, and can then name his oculars, like the objectives, either by their magnifying powers or by their equivalent focal lengths. The rivalry of makers and the interests of trade are not involved in this case as in that of the objectives, and there may be no reason why this plan, if as acceptable to microscopists generally, as it has been to a few, should not come into immediate use.
In order to work the objectives and oculars at their standard powers they should be of course, about ten inches apart either by length of compound body or In' use of draw tube ; and it is believed that most objectives whose corrections arc accurate enough to show any difference will work best at about this distance. Should a decidedly different distance be used in any observations of importance, it would be well to state that fact in recording the observation.
In reviewing this subject, the following points would seem to be reasonably well settled. Objectives should be, and could be to a much greater extent than they now are, rated according to a uniform standard. They should be named not arbitrarily, but in a manner indicative of their magnifying power. Ten inches is the standard distance of measurement in estimating powers. This distance should be taken from the eye to the rule by which the measurements are made, without regard to the distance of the object on the stage. Magnifying power is always stated in linear measure. The magnifying power and angular aperture, as well as the makers name, should be engraved on all objectives, and added to all particularly important drawings made by their means. Oculars should be named, like the objectives, in such manner as to indicate their magnifying powers or equivalent focal lengths.
The following are some of the more important queries which still remain open. Should the standard one-inch objective be characterized by magnifying ten diameters as used in the compound microscope, or should it be compared to a simple lens of actually measured focus or foci? Should the objective be named by, its equivalent focal length, or by its amplifying power, or both? Should our standard distance of measurement be changed from ten inches (254 millimetres) to nine and five-sixths inches ("250 millimetres)? From what point in the objective shall the distance to the scale be measured? At what point of screw-collar adjustment shall the objective be placed for rating its angular aperture and amplifying power? Should the name ocular be substituted for "eye-piece" in general use?
1-2 natural size.
There arc many people still living who remember the Indians in New Jersey, the last remnant of the once mighty tribe, the Lenni Lenape; and to-day scattered all over the state, from the mountains of Sussex to the sea-beach of Cape May, are to be found stone weapons and implements, popularly considered as once the property of these aborigines, and by them fashioned in all the varied shapes, sizes and of the various minerals that we now find. Axes, arrow-heads, lance-heads, javelins, harpoons, spears, knives, scrapers, hammers, adzes, mortars and pestles, pipes, amulets and puzzling shapes of chipped jasper; all these, in varying numbers are yearly turned up by the plough, gathered as "curiosities," or momentarily gazed upon and thrown aside to turn up again, more broken than before, and so more a puzzle to him who finds them. Again, at odd times, a "deposit" is met with, deep in the soil and a neighborhood may have the even tenor of its way disturbed by the wise comments of village sages, who ponder gravely over the "injine things" and never think to preserve them. A record of a number of these "finds," however, has put us in possession
1-2 natural size. 1-2 natural size.
of this fact, that the banks of our rivers and larger creeks were the favorite localities of these people of the stone age,— these Indians, if you choose — a people who had at no time a knowledge of metals, unless perhaps they utilized the many masses of native copper, which even a century ago were still to be found in some localities (neighborhood of New Brunswick, Middlesex and Somerset counties). There are yet savages in their stone age; and it was not many centuries ago that a people along the Delaware River fashioned from its sandstone and porphyry peb
AMBB. NATURALIST, VOL. VI. 10
bles the weapons and implements their primitive wants suggested. These "relies" are now (with exceptions to be mentioned hereafter) surface-found specimens; but when a hundred or more are gathered together and carefully compared, we must come to one of two conclusions; either that there were many execrable workmen among their tool makers; or that the age of the crude specri_ M imens far exceeds that of the
finely wrought relics. Compare the rude implement (Fig. 9) and the finely polished axe (Fig. 15). Both of these were found on the surface, yet we can scarcely imagine that n people who could fashion the latter, would deign to utilize the former. Take a series of whatever class of relics you may, there is always a gradation from poor (primitive) to good (elaborate), which is an indication, we believe, of a lapse of years from very ancient to more modern times, from a paleolithic to a neolithic age; and long after the introduction of metals, the choicer stone weapons were probably retained, and new ones continually manufactured. Arrow heads of stone, we know, are still in use. If this surmise be correct, if a people as rude as they who fashioned the wrought flints found at St. Acheul, near Amiens, France,* once dwelt on the shores of the Delaware, and the relics are as rude as those mentioned above, were not such a people too primitive to wander from another continent? We believe this and consider the first inhabitants along our Atlantic coast and inland to have been autochthones,f and that their "flint chips" are now found
• Nilsson on the Stone Age. Edited by Sir J. Lubbock. Page six, lip:, i. 3d Ed. 18G8.
f We Judge of our "Indians" by those relics that are now the only trace of their former existence, and llmling stone implement* as rude as those of Abbeville and Hoxne (see Lubbock's Prehistoric times), we naturally conclude that the fashioners of such •'flints" were so primitive as to be incapable of a migration from Asia, and
1-2 natural size.
mingled with the more elaborate stoneware of their descendants; the so-called Indians of to-day.
Having made a collection of these stone implements and weapons, it was natural to attempt to classify them at once, and
when we speak of things so
dissimilar as axes and arrow
heads, it seems strange that
there should be any doubt at
times, whether any particular specimen should belong
to one class or the other;
yet we have met with such
specimens, and our cabinet
contains an unbroken series
from the latter to the former,
from triangular arrow heads,
whose three sides scarce
measure an inch, to jasper
hatchets(?) a foot in length;
and these hatchets run as
gradually into axes, as the arrow points cease to be such,
and are javelins, lance heads, harpoons or spears, as fancy dictates.
through a country so bleak as to offer no Inducement to leave a more congenial climate. However, the Esquimaux seem to be contented where they are, but they are a very different people from the so-called •' Indians." We cannot but think th.it there was an autochthonlc people here in North America, and if an Asiatic people migrated hither, they drove away or absorbed the primitive race that utilized such rude implements, as one especially, that we have figured. We do not hesit'ite to state such to be our belief, notwithstanding we And Baron Bunsen saying, "The linguistic data before us [speaking of Schoolcraft's work on Indians], combined with the traditions and customs and. particularly, with the system of pictorial mnemonic writing (drst revealed in this work), enable me to say that the Asiatic origin of all these tribes is as fully proved as the unity of family among themselves." Sir John Lubbock says (Origin of Civilization; Amer. ed., p. 315), " It is nij- belief that the great continents were already occupied by a wide spread, though sparse, population, when man was no more advanced than the lowest savages of to-day, and although I am far from believing that the various degrees of civilization which now occur can be altogether accounted for by the external circumstances as they at present exist, still these circumstances seem to me ti> throw much light on the very different amount of progress which has been attained by different races." That is the migration from Asia that Ilunsen claimed has absorbed the preexisting race, but has not obliterated ill trices of such autochthonic people,— we say autochthonic, but if all mankind sprung from some catarrhine ape of the Old World, a migration to America must have occurred; but this is going so far back Into the past, that the relative positions of continent and oce:in may have been widely different from what now exists, or existed when Bunsen would date the Turanian migration from Asia.