them considerable weight in our average. Dr. Price's is so old, and so near the limit where we have thought proper to exclude the observations, that we shall allow it less weight than the others, but we shall not feel at liberty to exclude it entirely.

In column second at the end of this article is Dr. Price's Swedish table, and in the third column is the adjusted rate of mortality. The influence of adjustment is very slight, as the large numbers observed and the quinquennial intervals of ages of the living and the dying have prevented any serious anomalies.

In column fourth is Mr. Milne's Swedish table, and in the next column its adjusted mortality. Both adjustments are made in the same way, by taking the geometrical mean of five successive rates as the true amount for each age.

In the next two columns are the rates of mortality for the next two periods of twenty years, obtained from the observations published by Dr. Farr in the sixth volume of the registrar general's reports. The mode of construction which we have adopted is that proposed by Dr. Farr, but in adjusting we have taken the mean of seven consecutive rates of mortality instead of five, because the observations being given for every five years, the adjustment by fives was not so satisfactory.

The

The next table we will introduce (column eighth,) is founded on the observations in Norway, published by Dr. Farr in the same volume of his reports. These were officially communicated, and seem to be made with care. They extend from 1800 to 1840, but the ages of the living are only given for the last census in 1840. The table we have constructed is, therefore, only for the last ten years, from 1830 to 1840. mode of construction we have employed is the same we have used for the Carlisle observations, which, though more laborious, is more reliable than any of the methods proposed. The actual number of the living at each age being approximately obtained, the rates of mortality that will give the observed deaths for these numbers of the living are more likely to be correct than the rates that give the proper number of deaths in a stationary population.

The numbers of the living and the dying being smaller than for Sweden, and for ten years only, we shall give less weight to this Norway table than to the Swedish. The rates of mortality are, however, less, and nearer to Farr's.

The next table is derived from the observations of Mr. Finlaison, actuary of the National Debt Office in Great Britain. His report to Parlia ment was made in 1829, and gives the particulars of the deaths and ages of the government annuitants and of the nominees under the several government tontines, beginning as early as 1693, and ending in 1826. The facts are numerous, perfectly reliable, continued through a long series of years, and very carefully collected and arranged. Mr. Finlaison's results have not, however, been very much esteemed. They differ considerably from our best tables, and contain anomalies not found elsewhere. This arises, we think, from the selection of lives which would exert a greater influence in a tontine than in an insurance office. When a policy is first issued the insurer is known to be in perfect health. His physycian and the company's medical examiner, as well as the insured himself and his friend, unite in testifying to this fact. The rate of mortality at any particular age will therefore be very different among recent in

surers and among those who have been long insured. The difference is still greater in the tontines, since many of these persons were chosen because of their vigorous health and their promise of long life. The mortality among such persons soon after admission would be very different from the average rate for persons of the same age taken at random or among the members of an insurance company. And this is sufficient

to account for the irregularities in these tables. Besides, Mr. Finlaison did not use all the materials he had collected and published, but only a portion of them which he thought most worthy of confidence. His "tables of annuities, computed for the government," were founded only on "the Irish Tontine," "the Tontine of 1789," and that "of the Sinking Fund as observed to the end of the year 1822."

In the table we have inserted at the end of this article we have used all the observations of Mr. Finlaison, omitting only the first set, because founded on observations which were made before the middle of the last century; and the result is free from many of the anomalies of his tables, and every way more worthy of confidence. We have adjusted it precisely in the same manner he did for his tables. Thus, we have added together his two summaries, Nos. 8 and 15, and subtracted No. 1, comprising in our result 21,350 lives, of whom 12,275 yet survived in January, 1826. We have then obtained the ratio of the living and the dying at each age, and adjusted these ratios by taking the geometrical mean of five consecutive terms, and then of each three of these results, following precisely the same method as Mr. Finlaison. To this mean two corrections were applied to get the rate of mortality at 15, 16, etc., because it is the ratio of the living and the dying at the average age of 15, 16, etc. The rates finally obtained are to be found in column ninth at the end of this article. At the earlier ages when the influence of selection is felt, the table is quite irregular. But for the older ages, when this objection disappears, the large number of lives, the exactness and accuracy of the observations, and the absence of all withdrawals, make the figures worthy of more confidence.

We have inserted in column tenth the mean of Finlaison's two tables, but we do not think them worthy of much weight in the proposed combination.

In column eleventh is to be found Farr's Northampton, which is very different from Dr. Price's, partly because it is founded on recent observations, but mainly because it has been properly constructed from the numbers of the living and the dying. Dr. Price, with great ingenuity, supplied the numbers of the living from the ages of the dying; but his hypothesis, though better than those made by his contemporaries, was not an approximation to the truth for the younger ages. Farr's is deserving of every confidence. As it embraces the mortality for seven years, from 1838 to 1844, among a population nearly as large as Carlisle; as the facts on which it has been based have been observed with care, and the table constructed on correct principles, it is worth nearly as much as the Car

lisle table.

Price's Mortality Milne's Milne's Sweden, Sweden, Norway, Finlaison, Finl'son, Farr's Age. Sweden. adjust'd, Sweden, adjust'd. 1795-1815, 1815-35. 1825-35. 1715-1826, male, fe. North'n. 15.. 5899 .0064 6098 .0061 .0066 .0052 .0055 .0071 .0064 .0056

Price's Mortality Milne's Milne's Sweden, Sweden, Norway, Finlaison, Finl'son, Farr's Age. Sweden adjust'd. Sweden, adjust'd. 1795-1815. 1815-35. 1825-35. 1745-1826. male, fe. North'n.

Price's Mortality Milne's Milne's Sweden, Sweden, Norway, Finlaison, Finl'son, Farr's Age. Sweden. adjust'd. Sweden. adjust'd. 1795-1815.1615-85, 1825-35. 1745-1826, male, fe. North'n.

THE importance of the crime of forgery, and the confusion which it is capable of creating in the transaction of both public and private affairs, have in all time engaged the serious attention of the ministers of justice. Notwithstanding this, however, the arts of the forger have never received that attention, in an educational point of view, which the importance of the subject demands.

In the progress of civilization cupidity has very nearly attained the dignity of a science, and how to detect and how to avoid the arts of the counterfeiter has well nigh become a necessary part of commercial education.

Forgery, in law, may be defined to be the fraudulent making or alteration of any record, deed, writing, instrument, register, stamp, etc., to the prejudice of another man's rights. This broad field of operation is open to a great variety of means with the freest use of scientific principles. If we consult the records of this species of crime, we discover the arts of the forger to be contemporaneous with the advance of science. Indeed, the propagation of the truths of the science of chemistry, among all classes of society, seems not only to have facilitated the arts of the falsifier, but in some cases to have been available for obliterating the evidence of murder. The application of chemical processes in the perpetration of crime have, in some instances, demonstrated the greatest triumphs in that science; and had they been used for scientific purposes alone, they would have clothed their discoverers with imperishable honor. Photography-one of the brightest gems of modern chemistry-bas achieved some of its greatest exploits in efforts to elude the "bank-note detector."

But in the adaptation of the latest truths of science, the forger never forgets the ruder methods of his art, now reduced to an unprecedented degree of perfection. The smooth erasure, the over careful preserva

tion of important documents by the use of strengthening bands, inelegant blots, or over elegant penmanship, characterized by a great display of flourishes, are tricks of the trade as of yore; and when they are associated with scientific accomplishments, they are the more deceptive. The chemical agents most usually employed in forgery are muriatic acid, citric acid, oxalic acid, common salt, and other substances containing chlorine, and the chemicals of photography.

In view of the foregoing circumstances, the examination of suspected forgeries may be facilitated by dividing the processes into two classes, namely, physical and chemical.

I. PHYSICAL EXAMINATION.-In the physical examination of written instruments, semi-transparent spots or lines, strengthening strips or entire new backs, blots, heavy or rough lines, interlineations attested with ink of a different shade of color from that used in the main composition, or flourishes of penmanship, are all suspicious conditions. The forger, in order to hide the semi-transparency of an erasure, usually wears the paper in the line of it, by forced creasing, and then applies a strengthening strip or new back. "Worn out lines," or those which have been inserted in the place of others removed, are often mended in the same way. Torn edges or rents, as the effect, or instead of erasures, are usually repaired by patches, strips, or new backs. Various shades in the color of the ink may be the result of time only in old papers, or they may indicate the reaction of chemical agents in efforts to remove it. Irregularity in the written lines and roughness may be consequent upon a bad quality of paper, or be caused by washing the sizing out of the paper in an effort to remove the ink. Washing, also, may cause an apparent irregularity in the thickness of the paper, leaving spots, from which the sizing has been removed, more or less transparent and rough, and thus simulate or obscure other spots which have been erased. All writing paper, in the process of its preparation, is sized; that is to say, it has incorporated with it substances which hinder the penetration of ink or other fluids. When, therefore, the ink strokes are large, or spread into the texture of the paper, they indicate the tamperings of forgery. Where resin has been used for smoothing over an erased surface, the contrary effect results; the ink is but sparingly absorbed by the resin, the lines are fine and superficial, and of glossy appearance. Blots, too, may be the result of original composition in consequence of poor paper, of accidental moisture, of age, smoke, or scorching; it is important, therefore, to determine these conditions. In general, blots which are the result of badly sized paper, or of washing, are of circular shape, and present a regular fading shade of color from center to circumference. Blots, of brownish color and glossy, are usually produced by bistre or liquid-brown, and are indelible. Humidity, or moisture, which is liable to occur in papers not well cared for, or by accident, is equally liable to occur in any or every part of the paper. The destructive effects of humidity are sometimes counterfeited by the application of acetic or other strong acids, which more effectually destroy the ink by a partial or total destruction of the paper in the places to which the application is made; whereas mere moisture scarcely or not at all affects the texture of the paper, otherwise than by removing the sizing. Besides, the acids are usually applied in particular places-the usual temptation being to partially and not wholly destroy the papers subjected to this means of counterfeiting.