The efforts made by Fire Insurance Companies to collect accurate particulars of the state of their business, and the profit or loss on different classes of risks, evince at once their appreciation of correct statistical information and the difficulty of obtaining it. Most Offices of any standing keep registers in which risks are divided into distinct classes—such as cotton mills, corn mills, farm stock, dwelling-houses, carpenters' shops, &c. &c.; and in one set enter under their proper heads the sums insured, premiums received, and number of risks, so that they can tell from inspection how many corn or cotton mills, or other risks, they insure each year, the total sums insured on them, and the amounts of premiums received: while in another set they enter under their proper heads the number of corn or cotton mills, or other risks, in which loss has occurred, and the losses paid—so that by inspection they can see what losses have been sustained on each class. The difference between the premiums received and the losses paid, leaving expenses of management out of view, constitutes a surplus or deficiency from which they judge of the profit or loss on each class of their insurances.