But little can be done in the northern states except to prepare manure, and get sashes, tools, &c., in working order; but in sections of the country where there is little or no frost the hardier kinds of seeds and plants may be sown and planted, such as asparagus, cabbage, cauliflower, carrot, leek, lettuce, onion, parsnip, peas, spinach, turnip, &c. In any section where these seeds can be sown in open ground, it is an indication that hotbeds may be started for the sowing of such tender vegetables as tomatoes, egg and pepper plants, &c.; though, unless in the extreme southern states, hotbeds should not be started before the beginning or middle of February.
The heating and ventilating arrangements are much the same as in the lean-to, only the top sashes which open are on the back slope, and therefore do not interfere so much with the vines on the front slope.
There are no upright front sashes, but to facilitate ventilation there are ventilators d in the front wall, and the upper roof sashes are made to move up to FIG.
Burlington is the most important manufacturing centre in the state; among its manufactures are sashes, doors and blinds, boxes, furniture and wooden-ware, cotton and woollen goods, patent medicines, refrigerators, house furnishings, paper and machinery.
In 1905 the city's factory products were valued at $6,355,754, three-tenths of which was the value of lumber and planing mill products, including sashes, doors and blinds.