REVERSION. 
a whole reverberatory. When the middle 
of the capital is open, and only the sides 
close, so that there is only a half circulalion 
of the dame, it is called an half reverbera- 
tory. The reverberatory furnace is chiedy 
used in the fusion and calcination of metals 
and minerals, and on other occasions where 
the most intense heat is required, as in 
assaying, &c. Whence it is also called the 
melting furnace, and assaying furnace. 
REVERSION, a sum of money, estate, 
annuity, or any other kind of property, the 
possession of which is not to be obtained 
till after the expiration of a certain period 
of time, or till some event, as the failure of 
a life or lives, has happened. The present 
value of such property depends greatly on 
the current interest of money, for if money 
produced only three per cent, interest, a 
person giving 10001. for a reversionary 
estate relinquishes an annuity of 301., but 
if he could make dve per cent, interest of 
his money he gives up an annuity of 501., 
and consequently in the latter case he would 
expect a greater reversion than the former. 
The true value of a reversion therefore is 
that present sum which if improved at a 
given rate of interest, would at the period 
when the reversion comes into possession 
amount to its then actual value. This, with 
respect to sums receivable at the end of a 
certain number of years, is easily found by 
Table II. article Interest. 
Thus, if a person is entitled to 5001. at 
the end of ten years, and wishes to know 
its present worth : the value of one pound 
to be received at the end of this term, is, 
by the Table 613913, which multiplied by 
500 gives 3061. 19s. Id. for the present 
value of the reversion. In a similar manner 
the present worth of the reversion of an 
annuity or estate after a certain number of 
years may be found by Table II. article 
Annuities. 
Example 1. 'What is the present value 
of an annuity of 211. for the term of 30 
years, but which is not to commence till 
the expiratioh of 7 years from the present 
time? The present value of an annuity of 
one pound for 30 years, is, by the Table 
15,372451}/ which multiplied by 21 gives 
322,8214; but as each payment of the 
annuity is to be received 7 years later than 
if it commenced inimediately, this sum 
must be multiplied by the value of one 
pound to be received at the end of 7 
years, or, .710681, which gives 2291. 8s. 
5d. for the present worth of the rever- 
sion. 
Example 2. What is the present worth 
of a perpetual ammity of 501. to commence 
at the expiration of a lease of which 5 years, 
are unexpired? The value of a perpetual 
annuity commencing immediately is, at 5 
per cent, interest, 20 years purchase ; the 
value of an annuity for 5 years is, by the 
Table, 4,329477; the latter subtracted 
from the former, and the remainder mul- 
tiplied by 30, gives 7831. 10s. 6d. the value 
of the reversion. 
Reversionary interests dspending on a 
life or lives, particularly when several lives 
are concerned, form more intricate ques- 
tions; but the cases which most commonly 
occur may be resolved by the following 
problems. 
Problem 1. A sum of money is to be 
received at the death of a person, who is 
now of a given age ; what is Ihe value there- 
of in present money ? 
Subtract the value of the life from the 
perpetuity ; then, as the perpetuity is to 
the remainder, so is the proposed sum to its 
value in present money. 
Example. Let the age be 30 years, and 
the given sum 5001. Then the value of the 
life being 13,072 and the perpetuity 20, it 
will be, as 20 : 6,928 ; : 3001 : 1731. 4s. the 
value sought. 
Problem 2. To find the value of the re- 
version of one life after another. 
From the value of the life in expectation 
subtract the value of the two joint lives ; the 
remainder will be the required value of the 
reversion. 
Example. Let the age of the life in 
possession be 55 years, that of the life in 
expectation 20 years, and the annuity 1001. 
Then, by Table V. (article Annuities) the 
value of the two joint lives will be 8,216, 
which subtracted from 14,007 the value of 
the life in expectation, leaves 5,791 years 
purchase for the value of the reversion; 
which multiplied by the annuity, gives 
5791. 2s. its value in present money. 
Problem 3. To find the value of tlie 
reversion of two lives after one. 
From the value of the longest of the 
three lives subtract the value of the life in 
possession, the remainder will be the value 
of the reversion. 
Example. Let the age of the life in 
possession be 40 years, and the ages of the 
two lives in expectation be 20 and 65 years ; 
in this case, the value of the three lives 
being 15,902, and that of the life in posses- 
sion 11,837} the answer will be 4,065 years 
purchase : so that, if the annuity was to be 
. 5001. the value of the reversion would be 
20321. 10.S. 
